fluoxetine/olanzapine (Rx)

Brand and Other Names:Symbyax
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Dosing & Uses

AdultPediatricGeriatric

Dosage Forms & Strengths

fluoxetine/olanzapine

capsule

  • 25mg/3mg
  • 25mg/6mg
  • 50mg/6mg
  • 25mg/12mg
  • 50mg/12mg

Depression Associated with Bipolar I Disorder

Indicated for acute depressive episodes in bipolar I disorder

Initial: 25 mg/6 mg PO qDay in evening

If needed, may titrate with 25-50 mg fluoxetine/6-12 mg olanzapine; not to exceed 75 mg/18 mg per day

Treatment of Resistant Depression

Indicated for treatment resistant depression (ie, major depressive disorder in patients who do not respond to 2 separate trials of different antidepressants of adequate dose and duration in the current episode)

Initial: 25 mg/6 mg PO qDay in evening

If needed, may titrate with 25-50 mg fluoxetine/6-12 mg olanzapine; not to exceed 75 mg/18 mg per day

Dosage Modifications

Hypotensive diathesis, hepatic impairment, or slow metabolism: Initiate with 25 mg/3 mg to 25 mg/6 mg PO qDay

Slow metabolism observed in females, elderly, and nonsmokers

Discontinue gradually

Coadministration with other monoamine oxidase inhibitor (MAOI)s (eg, linezolid or methylene blue)

  • Do not start fluoxetine/olanzapine in patients treated with linezolid or IV methylene blue due to the increased risk of serotonin syndrome
  • If alternatives to linezolid or IV methylene blue treatment are not available and potential benefits of linezolid or intravenous methylene blue are judged to outweigh risks of serotonin syndrome, promptly stop fluoxetine/olanzapine, and linezolid or intravenous methylene blue can be administered
  • Monitor for symptoms of serotonin syndrome for 5 weeks or until 24 hr after the last dose of linezolid or IV methylene blue, whichever comes first; resume 24 hr after the last dose of linezolid or IV methylene blue

Dosing Considerations

Switching to or from a MAOIs to treat psychiatric disorders

  • Allow at least 14 days to elapse prior to starting fluoxetine/olanzapine after discontinuation of an MAOI intended to treat psychiatric disorders
  • Conversely, allow at least 5 weeks after stopping fluoxetine/olanzapine before starting an MAOI intended to treat psychiatric disorders

Dosage Forms & Strengths

fluoxetine/olanzapine

capsule

  • 25mg/3mg
  • 25mg/6mg
  • 50mg/6mg
  • 25mg/12mg
  • 50mg/12mg

Depression Associated with Bipolar I Disorder

Indicated for acute depressive episodes in bipolar I disorder in children and adolescents aged 10-17 years

<10 years: Safety and efficacy not established

10-17 years

  • Initial: 25 mg/3 mg PO qDay in evening
  • If needed, may titrate with 25-50 mg fluoxetine/6-12 mg olanzapine; not to exceed 50 mg/12 mg per day

Clinical studies of fluoxetine/olanzapine did not include sufficient numbers of patients ≥65 year; use with caution

Initiate with 25 mg/3 mg to 25 mg/6 mg PO qDay

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Interactions

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            Contraindicated (14)

            • artemether/lumefantrine

              artemether/lumefantrine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Contraindicated.

            • eliglustat

              fluoxetine increases levels of eliglustat by affecting hepatic enzyme CYP2D6 metabolism. Contraindicated. If coadministered with strong or moderate CYP2D6 inhibitors, reduce eliglustat dose from 84 mg BID to 84 mg once daily in extensive and intermediate metabolizers; eliglustat is contraindiated if strong or moderate CYP2D6 inhibitors are given concomitantly with strong or moderate CYP3A inhibitors.

            • goserelin

              goserelin increases toxicity of fluoxetine by QTc interval. Contraindicated. Increases risk of torsades de pointes.

            • isocarboxazid

              isocarboxazid and fluoxetine both increase serotonin levels. Contraindicated.

            • leuprolide

              leuprolide increases toxicity of fluoxetine by QTc interval. Contraindicated. Increases risk of torsades de pointes.

            • linezolid

              linezolid and fluoxetine both increase serotonin levels. Contraindicated. Linezolid may increase serotonin as a result of MAO-A inhibition. If linezolid must be administered, discontinue serotonergic drug immediately and monitor for CNS toxicity. Serotonergic therapy may be resumed 24 hours after last linezolid dose or after 5 weeks of monitoring, whichever comes first.

            • lumefantrine

              lumefantrine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Contraindicated.

            • methylene blue

              methylene blue and fluoxetine both increase serotonin levels. Contraindicated. Methylene blue may increase serotonin as a result of MAO-A inhibition. If methylene blue must be administered, discontinue fluoxetine immediately and monitor for CNS toxicity. Fluoxetine may be resumed 24 hours after last methylene blue dose or after 5 weeks of monitoring, whichever comes first.

            • phenelzine

              phenelzine and fluoxetine both increase serotonin levels. Contraindicated.

            • pimozide

              fluoxetine and pimozide both increase QTc interval. Contraindicated.

              fluoxetine increases levels of pimozide by decreasing metabolism. Contraindicated. Risk of QT interval prolongation.

            • procarbazine

              procarbazine and fluoxetine both increase serotonin levels. Contraindicated. Combinations is contraindicated within 5 weeks of MAOI use.

            • selegiline

              selegiline and fluoxetine both increase serotonin levels. Contraindicated. At least 5 weeks should elapse between discontinuation of fluoxetine and initiation of selegiline.

            • thioridazine

              thioridazine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Contraindicated.

              thioridazine and fluoxetine both increase QTc interval. Contraindicated.

              fluoxetine increases levels of thioridazine by decreasing metabolism. Contraindicated. Risk of long QT syndrome.

            • tranylcypromine

              tranylcypromine and fluoxetine both increase serotonin levels. Contraindicated.

            Serious - Use Alternative (146)

            • abametapir

              abametapir will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. For 2 weeks after abametapir application, avoid taking drugs that are CYP1A2 substrates. If not feasible, avoid use of abametapir.

            • alfentanil

              alfentanil, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • amiodarone

              amiodarone and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

            • amitriptyline

              fluoxetine will increase the level or effect of amitriptyline by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.

              fluoxetine and amitriptyline both increase serotonin levels. Avoid or Use Alternate Drug.

            • amoxapine

              fluoxetine and amoxapine both increase serotonin levels. Avoid or Use Alternate Drug.

            • apomorphine

              olanzapine decreases effects of apomorphine by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

              apomorphine and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • aripiprazole

              fluoxetine will increase the level or effect of aripiprazole by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              aripiprazole and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

            • arsenic trioxide

              arsenic trioxide and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

            • artemether

              artemether and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

              artemether and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • atomoxetine

              atomoxetine and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

            • benzhydrocodone/acetaminophen

              benzhydrocodone/acetaminophen, olanzapine. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

            • bromocriptine

              olanzapine decreases effects of bromocriptine by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • bupropion

              fluoxetine increases toxicity of bupropion by unspecified interaction mechanism. Avoid or Use Alternate Drug. May lower seizure threshold; keep bupropion dose as low as possible.

            • buspirone

              fluoxetine and buspirone both increase serotonin levels. Avoid or Use Alternate Drug.

            • cabergoline

              olanzapine decreases effects of cabergoline by pharmacodynamic antagonism. Contraindicated.

            • calcium/magnesium/potassium/sodium oxybates

              olanzapine, calcium/magnesium/potassium/sodium oxybates. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

            • carvedilol

              fluoxetine will increase the level or effect of carvedilol by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • ceritinib

              ceritinib and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

              ceritinib and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • chlorpromazine

              fluoxetine will increase the level or effect of chlorpromazine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • citalopram

              citalopram and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • cimetidine

              fluoxetine will increase the level or effect of cimetidine by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.

            • citalopram

              citalopram and fluoxetine both increase serotonin levels. Avoid or Use Alternate Drug. Combination may increase risk of serotonin syndrome or neuroleptic malignant syndrome-like reactions. ECG monitoring is recommended, along with drugs that may prolong the QT interval.

            • clarithromycin

              clarithromycin and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • clomipramine

              fluoxetine will increase the level or effect of clomipramine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              fluoxetine and clomipramine both increase serotonin levels. Avoid or Use Alternate Drug.

            • clopidogrel

              fluoxetine decreases effects of clopidogrel by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug. Clopidogrel efficacy may be reduced by drugs that inhibit CYP2C19. Inhibition of platelet aggregation by clopidogrel is entirely due to an active metabolite. Clopidogrel is metabolized to this active metabolite in part by CYP2C19. .

            • clozapine

              clozapine and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • crizotinib

              crizotinib and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • cyclobenzaprine

              fluoxetine and cyclobenzaprine both increase serotonin levels. Avoid or Use Alternate Drug.

            • dacomitinib

              dacomitinib will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug. Avoid use with CYP2D6 substrates where minimal increases in concentration of the CYP2D6 substrate may lead to serious or life-threatening toxicities.

            • degarelix

              degarelix and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • desflurane

              desflurane and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

              desflurane and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • desipramine

              fluoxetine will increase the level or effect of desipramine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              fluoxetine and desipramine both increase serotonin levels. Avoid or Use Alternate Drug.

            • dopamine

              olanzapine decreases effects of dopamine by pharmacodynamic antagonism. Contraindicated.

            • desvenlafaxine

              fluoxetine and desvenlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.

            • dextromethorphan

              fluoxetine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              fluoxetine and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.

            • disopyramide

              disopyramide and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

            • dolasetron

              dolasetron, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • dosulepin

              fluoxetine and dosulepin both increase serotonin levels. Avoid or Use Alternate Drug.

            • doxepin

              fluoxetine will increase the level or effect of doxepin by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              fluoxetine and doxepin both increase serotonin levels. Avoid or Use Alternate Drug.

            • duloxetine

              fluoxetine will increase the level or effect of duloxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              duloxetine and fluoxetine both increase serotonin levels. Avoid or Use Alternate Drug.

            • encorafenib

              encorafenib and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug. Encorafenib is associated with dose-dependent QTc interval prolongation. Avoid with drugs known to prolong QT interval.

            • entrectinib

              fluoxetine and entrectinib both increase QTc interval. Avoid or Use Alternate Drug.

              olanzapine and entrectinib both increase QTc interval. Avoid or Use Alternate Drug.

            • erdafitinib

              olanzapine will increase the level or effect of erdafitinib by affecting hepatic enzyme CYP2C9/10 metabolism. Avoid or Use Alternate Drug. If coadministration of a strong CYP2C9 inhibitors is unavoidable, closely monitor adverse reactions and modify dose of erdafitinib accordingly. If strong CYP2C9 inhibitor is discontinued, consider increasing erdafitinib dose in the absence of any drug-related toxicities.

            • escitalopram

              fluoxetine will increase the level or effect of escitalopram by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.

              escitalopram and fluoxetine both increase serotonin levels. Avoid or Use Alternate Drug.

            • fedratinib

              olanzapine will increase the level or effect of fedratinib by Other (see comment). Avoid or Use Alternate Drug. Avoid coadministration of fedratinib (a CYP3A4 and CYP2C19 substrate) with dual CYP3A4 and CYP2C19 inhibitor. Effect of coadministration of a dual CYP3A4 and CYP2C19 inhibitor with fedratinib has not been studied.

              fluoxetine will increase the level or effect of fedratinib by Other (see comment). Avoid or Use Alternate Drug. Avoid coadministration of fedratinib (a CYP3A4 and CYP2C19 substrate) with dual CYP3A4 and CYP2C19 inhibitor. Effect of coadministration of a dual CYP3A4 and CYP2C19 inhibitor with fedratinib has not been studied.

            • fentanyl

              fentanyl, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • fexinidazole

              fexinidazole and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Avoid coadministration of fexinidazole with drugs known to block potassium channels or prolong QT interval.

            • fentanyl intranasal

              fentanyl intranasal, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • fentanyl transdermal

              fentanyl transdermal, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • fentanyl transmucosal

              fentanyl transmucosal, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • fexinidazole

              fexinidazole and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug. Avoid coadministration of fexinidazole with drugs known to block potassium channels or prolong QT interval.

            • flecainide

              fluoxetine will increase the level or effect of flecainide by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • fluphenazine

              fluoxetine will increase the level or effect of fluphenazine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              fluphenazine and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

            • fluvoxamine

              fluvoxamine and fluoxetine both increase serotonin levels. Avoid or Use Alternate Drug.

              fluvoxamine will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.

            • gilteritinib

              gilteritinib will decrease the level or effect of fluoxetine by Other (see comment). Avoid or Use Alternate Drug. Coadministration of gilteritinib with drugs that inhibit 5HT2B or sigma nonspecific receptors. Avoid use of these drugs with gilteritinib unless coadministration is necessary.

            • givosiran

              givosiran will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP1A2 substrates with givosiran. If unavoidable, decrease the CYP1A2 substrate dosage in accordance with approved product labeling.

            • givosiran

              givosiran will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP2D6 substrates with givosiran. If unavoidable, decrease the CYP2D6 substrate dosage in accordance with approved product labeling.

            • glasdegib

              olanzapine and glasdegib both increase QTc interval. Avoid or Use Alternate Drug. If coadministration unavoidable, monitor for increased risk of QTc interval prolongation.

              fluoxetine and glasdegib both increase QTc interval. Avoid or Use Alternate Drug. If coadministration unavoidable, monitor for increased risk of QTc interval prolongation.

            • granisetron

              granisetron, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • hydrocodone

              hydrocodone, olanzapine. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

            • haloperidol

              fluoxetine will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              haloperidol will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • histrelin

              histrelin increases toxicity of fluoxetine by QTc interval. Avoid or Use Alternate Drug. Increases risk of torsades de pointes.

            • hydromorphone

              fluoxetine will increase the level or effect of hydromorphone by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              hydromorphone, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • hydroxychloroquine sulfate

              hydroxychloroquine sulfate and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

              hydroxychloroquine sulfate and olanzapine both increase QTc interval. Avoid or Use Alternate Drug.

            • hydroxyzine

              hydroxyzine increases toxicity of fluoxetine by QTc interval. Avoid or Use Alternate Drug. Increases risk of torsades de pointes.

            • ivosidenib

              ivosidenib and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Avoid coadministration of QTc prolonging drugs with ivosidenib or replace with alternate therapies. If coadministration of a QTc prolonging drug is unavoidable, monitor for increased risk of QTc interval prolongation.

            • ibutilide

              fluoxetine and ibutilide both increase QTc interval. Avoid or Use Alternate Drug.

            • iloperidone

              fluoxetine will increase the level or effect of iloperidone by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • imipramine

              fluoxetine will increase the level or effect of imipramine by affecting hepatic enzyme CYP2C19 metabolism. Avoid or Use Alternate Drug.

              fluoxetine will increase the level or effect of imipramine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              fluoxetine and imipramine both increase serotonin levels. Avoid or Use Alternate Drug.

            • indapamide

              fluoxetine and indapamide both increase QTc interval. Avoid or Use Alternate Drug.

            • ivosidenib

              ivosidenib and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug. Avoid coadministration of QTc prolonging drugs with ivosidenib or replace with alternate therapies. If coadministration of a QTc prolonging drug is unavoidable, monitor for increased risk of QTc interval prolongation.

              ivosidenib will decrease the level or effect of fluoxetine by affecting hepatic enzyme CYP2C9/10 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP2C9 substrates with ivosidenib or replace with alternate therapies. If coadministration is unavoidable, monitor patients for loss of therapeutic effect of these drugs.

            • lefamulin

              lefamulin and olanzapine both increase QTc interval. Avoid or Use Alternate Drug.

              lefamulin and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

            • levodopa

              olanzapine decreases effects of levodopa by pharmacodynamic antagonism. Avoid or Use Alternate Drug.

            • levomilnacipran

              fluoxetine and levomilnacipran both increase serotonin levels. Avoid or Use Alternate Drug.

            • levodopa inhaled

              olanzapine decreases effects of levodopa inhaled by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Atypical (2nd generation) antipsychotics inhibit dopamine D2 receptors in varying degrees (clozapine and quetiapine are lower risk). .

            • lisuride

              olanzapine decreases effects of lisuride by pharmacodynamic antagonism. Contraindicated.

            • lofepramine

              fluoxetine will increase the level or effect of lofepramine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              fluoxetine and lofepramine both increase serotonin levels. Avoid or Use Alternate Drug.

            • lonafarnib

              fluoxetine will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of lonafarnib (a sensitive CYP3A substrate) with weak CYP3A inhibitors is unavoidable, reduce to, or continue lonafarnib at starting dose. Closely monitor for arrhythmias and events (eg, syncope, heart palpitations) since lonafarnib effect on QT interval is unknown.

              olanzapine will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of lonafarnib (a sensitive CYP3A substrate) with weak CYP3A inhibitors is unavoidable, reduce to, or continue lonafarnib at starting dose. Closely monitor for arrhythmias and events (eg, syncope, heart palpitations) since lonafarnib effect on QT interval is unknown.

            • lorcaserin

              fluoxetine and lorcaserin both increase serotonin levels. Avoid or Use Alternate Drug.

            • macimorelin

              macimorelin and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. Macimorelin causes an increase of ~11 msec in the corrected QT interval. Avoid coadministration with drugs that prolong QT interval, which could increase risk for developing torsade de pointes-type ventricular tachycardia. Allow sufficient washout time of drugs that are known to prolong the QT interval before administering macimorelin.

            • macimorelin

              macimorelin and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug. Macimorelin causes an increase of ~11 msec in the corrected QT interval. Avoid coadministration with drugs that prolong QT interval, which could increase risk for developing torsade de pointes-type ventricular tachycardia. Allow sufficient washout time of drugs that are known to prolong the QT interval before administering macimorelin.

            • maprotiline

              fluoxetine and maprotiline both increase serotonin levels. Avoid or Use Alternate Drug.

            • mefloquine

              mefloquine increases toxicity of olanzapine by QTc interval. Avoid or Use Alternate Drug. Mefloquine may enhance the QTc prolonging effect of high risk QTc prolonging agents.

              mefloquine increases toxicity of fluoxetine by QTc interval. Avoid or Use Alternate Drug. Mefloquine may enhance the QTc prolonging effect of high risk QTc prolonging agents.

            • meperidine

              fluoxetine and meperidine both increase serotonin levels. Avoid or Use Alternate Drug.

              meperidine, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • methyldopa

              olanzapine decreases effects of methyldopa by pharmacodynamic antagonism. Contraindicated.

            • methamphetamine

              fluoxetine will increase the level or effect of methamphetamine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • methylenedioxymethamphetamine

              fluoxetine increases toxicity of methylenedioxymethamphetamine by decreasing elimination. Contraindicated.

            • metoclopramide

              metoclopramide and fluoxetine both increase serotonin levels. Avoid or Use Alternate Drug. Additive effects; increased risk for serotonin syndrome, neuroleptic malignant syndrome, dystonia, or other extrapyramidal reactions

            • metoclopramide intranasal

              olanzapine increases toxicity of metoclopramide intranasal by pharmacodynamic synergism. Avoid or Use Alternate Drug. Potential for additive effects, including increased frequency and severity of tardive dyskinesia, other extrapyramidal symptoms, and neuroleptic malignant syndrome.

              olanzapine, metoclopramide intranasal. Either increases effects of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Avoid use of metoclopramide intranasal or interacting drug, depending on importance of drug to patient.

              fluoxetine, metoclopramide intranasal. Either increases effects of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Avoid use of metoclopramide intranasal or interacting drug, depending on importance of drug to patient.

              fluoxetine will increase the level or effect of metoclopramide intranasal by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug. Concurrent use of metoclopramide intranasal and strong CYP2D6 inhibitors is not recommended since the metoclopramide intranasal dose cannot be adjusted.

            • metoprolol

              fluoxetine will increase the level or effect of metoprolol by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • mobocertinib

              mobocertinib and olanzapine both increase QTc interval. Avoid or Use Alternate Drug. If coadministration unavoidable, reduce mobocertinib dose and monitor QTc interval more frequently.

            • mexiletine

              fluoxetine will increase the level or effect of mexiletine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • milnacipran

              fluoxetine and milnacipran both increase serotonin levels. Avoid or Use Alternate Drug.

            • mobocertinib

              mobocertinib and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug. If coadministration unavoidable, reduce mobocertinib dose and monitor QTc interval more frequently.

            • morphine

              fluoxetine will increase the level or effect of morphine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              morphine, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • nebivolol

              fluoxetine will increase the level or effect of nebivolol by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • nefazodone

              fluoxetine and nefazodone both increase serotonin levels. Avoid or Use Alternate Drug.

            • netupitant/palonosetron

              netupitant/palonosetron, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • nortriptyline

              fluoxetine will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              fluoxetine and nortriptyline both increase serotonin levels. Avoid or Use Alternate Drug.

            • ondansetron

              fluoxetine and ondansetron both increase QTc interval. Avoid or Use Alternate Drug. Avoid with congenital long QT syndrome; ECG monitoring recommended with concomitant medications that prolong QT interval, electrolyte abnormalities, CHF, or bradyarrhythmias.

              ondansetron, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

              olanzapine and ondansetron both increase QTc interval. Avoid or Use Alternate Drug. Avoid with congenital long QT syndrome; ECG monitoring recommended with concomitant medications that prolong QT interval, electrolyte abnormalities, CHF, or bradyarrhythmias.

            • oxycodone

              oxycodone will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug. Opioids may enhance the serotonergic effects of SSRIs and increase risk for serotonergic syndrome

            • pefloxacin

              pefloxacin will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug.

            • oxymorphone

              fluoxetine will increase the level or effect of oxymorphone by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • ozanimod

              ozanimod increases toxicity of fluoxetine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Because the active metabolite of ozanimod inhibits MAO-B in vitro, there is a potential for serious adverse reactions, including hypertensive crisis. Therefore, coadministration of ozanimod with drugs that can increase norepinephrine or serotonin is not recommended. Monitor for hypertension with concomitant use.

            • palonosetron

              palonosetron, fluoxetine. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug.

            • panobinostat

              fluoxetine and panobinostat both increase QTc interval. Avoid or Use Alternate Drug. Panobinostat is known to significantly prolong QT interval. Panobinostat prescribing information states use with drugs known to prolong QTc is not recommended.

            • paroxetine

              fluoxetine will increase the level or effect of paroxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              fluoxetine and paroxetine both increase serotonin levels. Avoid or Use Alternate Drug.

            • pentamidine

              fluoxetine and pentamidine both increase QTc interval. Avoid or Use Alternate Drug.

            • perphenazine

              fluoxetine will increase the level or effect of perphenazine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              perphenazine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              perphenazine and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

            • phentermine

              fluoxetine, phentermine. Either increases toxicity of the other by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of serotonin syndrome.

            • pirfenidone

              fluoxetine will increase the level or effect of pirfenidone by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. Avoid; coadministration of pirfenidone and moderate CYP1A2 inhibitors result in moderately increased exposure to pirfenidone; if unable to avoid, decrease dose of moderate CYP1A2 inhibitor

            • pitolisant

              olanzapine and pitolisant both increase QTc interval. Avoid or Use Alternate Drug.

              fluoxetine and pitolisant both increase QTc interval. Avoid or Use Alternate Drug.

            • pramipexole

              olanzapine decreases effects of pramipexole by pharmacodynamic antagonism. Contraindicated.

            • procainamide

              fluoxetine and procainamide both increase QTc interval. Avoid or Use Alternate Drug.

            • promethazine

              fluoxetine will increase the level or effect of promethazine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • propafenone

              fluoxetine will increase the level or effect of propafenone by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              propafenone will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              propafenone and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

            • propranolol

              fluoxetine will increase the level or effect of propranolol by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • protriptyline

              fluoxetine and protriptyline both increase serotonin levels. Avoid or Use Alternate Drug.

            • quinidine

              quinidine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              quinidine and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug.

            • rasagiline

              rasagiline and fluoxetine both increase serotonin levels. Avoid or Use Alternate Drug. evere CNS toxicity associated with hyperpyrexia has been reported with the combined treatment of an antidepressant and rasagiline. Avoid combination within 14 days of MAOI use.

            • ribociclib

              ribociclib increases toxicity of fluoxetine by QTc interval. Avoid or Use Alternate Drug.

              ribociclib will increase the level or effect of fluoxetine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

              ribociclib increases toxicity of olanzapine by QTc interval. Avoid or Use Alternate Drug. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances.

            • risperidone

              fluoxetine will increase the level or effect of risperidone by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • ropinirole

              olanzapine decreases effects of ropinirole by pharmacodynamic antagonism. Contraindicated.

            • safinamide

              olanzapine decreases effects of safinamide by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Dopamine antagonists may decrease safinamide effects and exacerbate Parkinson disease symptoms.

            • selegiline transdermal

              selegiline transdermal and fluoxetine both decrease serotonin levels. Avoid or Use Alternate Drug.

            • selinexor

              selinexor, fluoxetine. unspecified interaction mechanism. Avoid or Use Alternate Drug. Patients treated with selinexor may experience neurological toxicities. Avoid taking selinexor with other medications that may cause dizziness or confusion.

              selinexor, olanzapine. unspecified interaction mechanism. Avoid or Use Alternate Drug. Patients treated with selinexor may experience neurological toxicities. Avoid taking selinexor with other medications that may cause dizziness or confusion.

            • sertraline

              sertraline will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

              fluoxetine and sertraline both increase serotonin levels. Avoid or Use Alternate Drug.

            • siponimod

              olanzapine will increase the level or effect of siponimod by affecting hepatic enzyme CYP2C9/10 metabolism. Avoid or Use Alternate Drug. Coadministration of siponimod with drugs that cause moderate CYP2C9 AND a moderate or strong CYP3A4 inhibition is not recommended. Caution if siponimod coadministered with moderate CYP2C9 inhibitors alone.

            • sodium oxybate

              olanzapine, sodium oxybate. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

            • sotalol

              fluoxetine and sotalol both increase QTc interval. Avoid or Use Alternate Drug.

            • St John's Wort

              fluoxetine and St John's Wort both increase serotonin levels. Avoid or Use Alternate Drug.

            • sufentanil SL

              sufentanil SL, olanzapine. Either increases toxicity of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration may result in hypotension, profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

            • tedizolid

              tedizolid, fluoxetine. Either increases effects of the other by Mechanism: pharmacodynamic synergism. Avoid or Use Alternate Drug. both increase serotonin levels; increased risk of serotonin syndrome.

            • thioridazine

              fluoxetine will increase the level or effect of thioridazine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • timolol

              fluoxetine will increase the level or effect of timolol by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • tipranavir

              tipranavir will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • tolterodine

              fluoxetine will increase the level or effect of tolterodine by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.

            • trazodone

              fluoxetine and trazodone both increase serotonin levels. Avoid or Use Alternate Drug.

            • trimipramine

              fluoxetine and trimipramine both increase serotonin levels. Avoid or Use Alternate Drug.

            • triptorelin

              triptorelin increases toxicity of fluoxetine by QTc interval. Avoid or Use Alternate Drug. Increases risk of torsades de pointes.

            • umeclidinium bromide/vilanterol inhaled

              olanzapine increases toxicity of umeclidinium bromide/vilanterol inhaled by QTc interval. Avoid or Use Alternate Drug. Exercise extreme caution when vilanterol coadministered with drugs that prolong QTc interval; adrenergic agonist effects on the cardiovascular system may be potentiated.

            • vandetanib

              fluoxetine, vandetanib. Either increases toxicity of the other by QTc interval. Avoid or Use Alternate Drug. Avoid coadministration with drugs known to prolong QT interval; if a drug known to prolong QT interval must be used, more frequent ECG monitoring is recommended.

            • vemurafenib

              vemurafenib and fluoxetine both increase QTc interval. Avoid or Use Alternate Drug. Concomitant use of vemurafenib with drugs that prolong QT interval is not recommended.

            • venlafaxine

              fluoxetine and venlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.

            • vilanterol/fluticasone furoate inhaled

              olanzapine increases toxicity of vilanterol/fluticasone furoate inhaled by QTc interval. Avoid or Use Alternate Drug. Exercise extreme caution when vilanterol coadministered with drugs that prolong QTc interval; adrenergic agonist effects on the cardiovascular system may be potentiated.

            • vilazodone

              fluoxetine, vilazodone. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug. Concomitant therapy should be discontinued immediately if signs or symptoms of serotonin syndrome emerge and supportive symptomatic treatment should be initiated. .

            Monitor Closely (526)

            • 5-HTP

              fluoxetine and 5-HTP both increase serotonin levels. Modify Therapy/Monitor Closely.

            • abiraterone

              abiraterone increases levels of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Avoid coadministration of abiraterone with substrates of CYP2D6. If alternative therapy cannot be used, exercise caution and consider a dose reduction of the CYP2D6 substrate.

            • abobotulinumtoxinA

              abobotulinumtoxinA increases effects of olanzapine by pharmacodynamic synergism. Use Caution/Monitor. Use of anticholinergic drugs after administration of botulinum toxin-containing products may potentiate systemic anticholinergic effects.

            • acarbose

              olanzapine, acarbose. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • aceclofenac

              fluoxetine, aceclofenac. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • acemetacin

              fluoxetine, acemetacin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • aclidinium

              aclidinium decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              aclidinium decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of aclidinium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • albiglutide

              olanzapine, albiglutide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • albuterol

              albuterol and fluoxetine both increase QTc interval. Use Caution/Monitor.

              olanzapine increases and albuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

              albuterol and olanzapine both increase QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • alfentanil

              alfentanil and olanzapine both increase sedation. Use Caution/Monitor.

            • alfuzosin

              alfuzosin and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

              fluoxetine and alfuzosin both increase QTc interval. Use Caution/Monitor.

            • alfuzosin

              olanzapine and alfuzosin both increase QTc interval. Use Caution/Monitor.

              alfuzosin and olanzapine both increase QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • almotriptan

              almotriptan and fluoxetine both increase serotonin levels. Modify Therapy/Monitor Closely.

              almotriptan, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • alosetron

              fluoxetine will increase the level or effect of alosetron by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

            • alprazolam

              alprazolam and olanzapine both increase sedation. Use Caution/Monitor.

            • alpelisib

              alpelisib will decrease the level or effect of fluoxetine by affecting hepatic enzyme CYP2C9/10 metabolism. Modify Therapy/Monitor Closely.

            • amifampridine

              fluoxetine increases toxicity of amifampridine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Amifampridine can cause seizures. Coadministration with drugs that lower seizure threshold may increase this risk.

            • amifostine

              amifostine, olanzapine. Either increases effects of the other by anti-hypertensive channel blocking. Use Caution/Monitor. Due to its alpha adrenergic antagonism, atypical antipsychotic agents has the potential to enhance the effect of certain antihypertensive agents. Monitor blood pressure and adjust dose accordingly.

            • amiodarone

              amiodarone will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

            • amitriptyline

              amitriptyline and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

              olanzapine and amitriptyline both increase sedation. Use Caution/Monitor.

            • amobarbital

              amobarbital will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

              amobarbital and olanzapine both increase sedation. Use Caution/Monitor.

            • amoxapine

              amoxapine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • amoxapine

              olanzapine and amoxapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              olanzapine and amoxapine both increase sedation. Use Caution/Monitor.

            • anticholinergic/sedative combos

              anticholinergic/sedative combos decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              anticholinergic/sedative combos decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of anticholinergic/sedative combos by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • apalutamide

              apalutamide will decrease the level or effect of fluoxetine by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. Coadministration of apalutamide, a weak CYP2C9 inducer, with drugs that are CYP2C9 substrates can result in lower exposure to these medications. Evaluate for loss of therapeutic effect if medication must be coadministered.

            • apixaban

              fluoxetine increases effects of apixaban by anticoagulation. Use Caution/Monitor. SSRIs may inhibit platelet aggregation, thus increase bleeding risk when coadministered with anticoagulants.

            • apomorphine

              apomorphine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

              olanzapine and apomorphine both increase sedation. Use Caution/Monitor.

            • arformoterol

              arformoterol and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

              arformoterol and olanzapine both increase QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

              olanzapine increases and arformoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • aripiprazole

              aripiprazole and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              aripiprazole and olanzapine both increase sedation. Use Caution/Monitor.

              aripiprazole and olanzapine both increase QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • artemether/lumefantrine

              fluoxetine and artemether/lumefantrine both increase QTc interval. Modify Therapy/Monitor Closely.

            • armodafinil

              armodafinil will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

              olanzapine increases and armodafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • asenapine

              asenapine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

              asenapine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • aspirin

              fluoxetine, aspirin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • aspirin rectal

              fluoxetine, aspirin rectal. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • aspirin/citric acid/sodium bicarbonate

              fluoxetine, aspirin/citric acid/sodium bicarbonate. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • atogepant

              fluoxetine will increase the level or effect of atogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

            • atomoxetine

              fluoxetine will increase the level or effect of atomoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Reduced initial doses of atomoxetine are recommended with strong CYP2D6 inhibitors.

              atomoxetine and olanzapine both increase QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • atracurium

              atracurium decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              atracurium decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of atracurium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • avapritinib

              fluoxetine will increase the level or effect of avapritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

            • atropine

              atropine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              atropine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of atropine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • atropine IV/IM

              olanzapine increases effects of atropine IV/IM by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

              atropine IV/IM decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              atropine IV/IM decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

            • avapritinib

              olanzapine will increase the level or effect of avapritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

            • axitinib

              fluoxetine increases levels of axitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

              olanzapine increases levels of axitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

            • azelastine

              azelastine and olanzapine both increase sedation. Use Caution/Monitor.

            • bedaquiline

              fluoxetine and bedaquiline both increase QTc interval. Modify Therapy/Monitor Closely. ECG should be monitored closely

            • azithromycin

              azithromycin increases toxicity of olanzapine by QTc interval. Use Caution/Monitor.

            • baclofen

              baclofen and olanzapine both increase sedation. Use Caution/Monitor.

            • bedaquiline

              olanzapine and bedaquiline both increase QTc interval. Modify Therapy/Monitor Closely. ECG should be monitored closely

            • belladonna alkaloids

              belladonna alkaloids decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              belladonna alkaloids decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of belladonna alkaloids by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • belladonna and opium

              belladonna and opium and olanzapine both increase sedation. Use Caution/Monitor.

              belladonna and opium decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              belladonna and opium decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of belladonna and opium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • benazepril

              olanzapine, benazepril. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Enhanced hypotensive effects.

            • benperidol

              benperidol and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              benperidol and olanzapine both increase sedation. Use Caution/Monitor.

            • benzhydrocodone/acetaminophen

              benzhydrocodone/acetaminophen, fluoxetine. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Coadministration of drugs that affect the serotonergic neurotransmitter system may result in serotonin syndrome. If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation and dose adjustment.

            • benzphetamine

              olanzapine increases and benzphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • benztropine

              olanzapine increases effects of benztropine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic adverse effects may be seen with concurrent use. .

            • betrixaban

              fluoxetine increases effects of betrixaban by anticoagulation. Use Caution/Monitor. SSRIs may inhibit platelet aggregation, thus increase bleeding risk when coadministered with anticoagulants.

            • bosentan

              fluoxetine will increase the level or effect of bosentan by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

            • brexanolone

              brexanolone, olanzapine. Either increases toxicity of the other by sedation. Use Caution/Monitor.

            • brexpiprazole

              fluoxetine will increase the level or effect of brexpiprazole by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Administer half of the usual brexpiprazole dose when coadministered with strong CYP2D6 inhibitors. If also administered with a strong/moderate CYP3A4 inhibitor, administer a quarter of brexpiprazole dose. NOTE: In MDD clinical trials, brexpiprazole dosage was not adjusted for strong CYP2D6 inhibitors (eg, paroxetine, fluoxetine); thus, CYP considerations are already factored into general dosing recommendations and brexpiprazole may be administered without dosage adjustment in patients with MDD.

            • brompheniramine

              brompheniramine and olanzapine both increase sedation. Use Caution/Monitor.

            • buprenorphine

              buprenorphine and olanzapine both increase sedation. Use Caution/Monitor.

            • buprenorphine buccal

              buprenorphine buccal and olanzapine both increase sedation. Use Caution/Monitor.

            • buprenorphine subdermal implant

              fluoxetine, buprenorphine subdermal implant. Either increases toxicity of the other by serotonin levels. Use Caution/Monitor. Concomitant use could result in life-threatening serotonin syndrome. If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation, and during dose adjustment of the serotonergic drug. Discontinue buprenorphine if serotonin syndrome is suspected.

            • buprenorphine, long-acting injection

              olanzapine increases toxicity of buprenorphine, long-acting injection by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of buprenorphine and benzodiazepines or other CNS depressants increases risk of adverse reactions including overdose, respiratory depression, and death. Cessation of benzodiazepines or other CNS depressants is preferred in most cases. In some cases, monitoring at a higher level of care for tapering CNS depressants may be appropriate. In others, gradually tapering a patient off of a prescribed benzodiazepine or other CNS depressant or decreasing to the lowest effective dose may be appropriate.

              fluoxetine, buprenorphine, long-acting injection. Either increases toxicity of the other by serotonin levels. Use Caution/Monitor. Concomitant use could result in life-threatening serotonin syndrome. If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation, and during dose adjustment of the serotonergic drug. Discontinue buprenorphine if serotonin syndrome is suspected.

            • bupropion

              bupropion will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

            • butabarbital

              butabarbital will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

              butabarbital and olanzapine both increase sedation. Use Caution/Monitor.

            • butalbital

              butalbital will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

              butalbital and olanzapine both increase sedation. Use Caution/Monitor.

            • butorphanol

              butorphanol and olanzapine both increase sedation. Use Caution/Monitor.

            • caffeine

              olanzapine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • cannabidiol

              fluoxetine will increase the level or effect of cannabidiol by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Consider reducing the cannabidiol dose when coadministered with a moderate CYP2C19 inhibitor.

              cannabidiol, olanzapine. affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Owing to the potential for both CYP1A2 induction and inhibition with the coadministration of CYP1A2 substrates and cannabidiol, consider reducing dosage adjustment of CYP1A2 substrates as clinically appropriate.

              cannabidiol will increase the level or effect of fluoxetine by decreasing metabolism. Modify Therapy/Monitor Closely. Cannabidiol may potentially inhibit CYP2C9 activity. Consider reducing the dose when concomitantly using CYP2C9 substrates.

            • captopril

              olanzapine, captopril. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs lower blood pressure. Monitor blood pressure.

            • carbamazepine

              fluoxetine will increase the level or effect of carbamazepine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor plasma levels when used concomitantly

            • carbamazepine

              carbamazepine will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • carbinoxamine

              carbinoxamine and olanzapine both increase sedation. Use Caution/Monitor.

            • carisoprodol

              carisoprodol and olanzapine both increase sedation. Use Caution/Monitor.

            • carvedilol

              fluoxetine will increase the level or effect of carvedilol by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

            • celecoxib

              fluoxetine will increase the level or effect of celecoxib by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

              celecoxib will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

              fluoxetine, celecoxib. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • chloral hydrate

              chloral hydrate and olanzapine both increase sedation. Use Caution/Monitor.

            • chlordiazepoxide

              chlordiazepoxide and olanzapine both increase sedation. Use Caution/Monitor.

            • chloroquine

              chloroquine increases toxicity of olanzapine by QTc interval. Use Caution/Monitor.

            • chlorpheniramine

              chlorpheniramine and olanzapine both increase sedation. Use Caution/Monitor.

            • chlorpromazine

              chlorpromazine and olanzapine both increase sedation. Use Caution/Monitor.

              chlorpromazine and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              chlorpromazine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • chlorpropamide

              fluoxetine increases effects of chlorpropamide by unspecified interaction mechanism. Use Caution/Monitor. Risk of hypoglycemia.

              olanzapine, chlorpropamide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • chlorzoxazone

              chlorzoxazone and olanzapine both increase sedation. Use Caution/Monitor.

            • choline magnesium trisalicylate

              fluoxetine, choline magnesium trisalicylate. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • cigarette smoking

              cigarette smoking will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • cilostazol

              fluoxetine increases toxicity of cilostazol by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Consider decreasing cilostazol dose; moderate CYP2C19 inhibitors may increase serum levels of 3,4-dehydrocilostazol (active metabolite).

            • cimetidine

              cimetidine will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

              cimetidine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

            • cinnarizine

              cinnarizine and olanzapine both increase sedation. Use Caution/Monitor.

            • ciprofloxacin

              ciprofloxacin and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • ciprofloxacin

              ciprofloxacin will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. Olanzapine plasma concentrations may be elevated, increasing the risk of adverse reactions such as orthostatic hypotension or sedation. It is important to use caution and observe patient and adjust the olanzapine dosage as needed.

            • cisatracurium

              cisatracurium decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              cisatracurium decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of cisatracurium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • citalopram

              citalopram and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • clarithromycin

              clarithromycin and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • clemastine

              clemastine and olanzapine both increase sedation. Use Caution/Monitor.

            • clobazam

              olanzapine, clobazam. Other (see comment). Use Caution/Monitor. Comment: Concomitant administration can increase the potential for CNS effects (e.g., increased sedation or respiratory depression).

              clobazam will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Lower doses of drugs metabolized by CYP2D6 may be required when used concomitantly.

            • clomipramine

              olanzapine and clomipramine both increase sedation. Use Caution/Monitor.

              clomipramine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • clonazepam

              clonazepam and olanzapine both increase sedation. Use Caution/Monitor.

            • clonidine

              clonidine, fluoxetine. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration enhances CNS depressant effects.

            • clonidine

              clonidine, olanzapine. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Additive hypotensive effects; potential delirium.

            • clopidogrel

              fluoxetine increases effects of clopidogrel by pharmacodynamic synergism. Use Caution/Monitor. SSRIs affect platelet activation; coadministration of SSRIs with clopidogrel may increase the risk of bleeding.

            • clorazepate

              clorazepate and olanzapine both increase sedation. Use Caution/Monitor.

            • clozapine

              fluoxetine increases levels of clozapine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Plasma levels of clozapine may be increased, resulting in increased pharmacologic and toxic effects. Adjust clozapine dose as needed when initiating or discontinuing certain SSRIs. .

              clozapine and olanzapine both increase sedation. Use Caution/Monitor.

              clozapine and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              clozapine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • cobicistat

              cobicistat will increase the level or effect of fluoxetine by Other (see comment). Use Caution/Monitor. Carefully titrate dose of the antidepressant to the desired effect, including using the lowest feasible initial or maintenance dose, and monitor its response during coadministration with SSRIs and cobicistat.

            • codeine

              codeine and olanzapine both increase sedation. Use Caution/Monitor.

            • cocaine

              fluoxetine and cocaine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • codeine

              fluoxetine will decrease the level or effect of codeine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Prevents conversion of codeine to its active metabolite morphine

            • crizotinib

              crizotinib and fluoxetine both increase QTc interval. Use Caution/Monitor. ECG monitoring is recommended, along with drugs that may prolong the QT interval.

            • cyclizine

              cyclizine and olanzapine both increase sedation. Use Caution/Monitor.

              cyclizine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              cyclizine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of cyclizine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • cyclobenzaprine

              cyclobenzaprine and olanzapine both increase sedation. Use Caution/Monitor.

              cyclobenzaprine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              cyclobenzaprine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of cyclobenzaprine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • cyproheptadine

              cyproheptadine decreases effects of fluoxetine by pharmacodynamic antagonism. Use Caution/Monitor. Cyproheptadine may diminish the serotonergic effect of SSRIs.

              cyproheptadine and olanzapine both increase sedation. Use Caution/Monitor.

            • dantrolene

              dantrolene and olanzapine both increase sedation. Use Caution/Monitor.

            • darunavir

              darunavir will increase the level or effect of fluoxetine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration with SSRIs, TCAs, or trazodone may require dose titration of antidepressant to desired effect (eg, using the lowest feasible initial or maintenance dose). Monitor for antidepressant response.

            • darifenacin

              darifenacin decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              darifenacin decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of darifenacin by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • dasatinib

              dasatinib and olanzapine both increase QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

              dasatinib and fluoxetine both increase QTc interval. Use Caution/Monitor.

            • deferasirox

              deferasirox will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • defibrotide

              defibrotide increases effects of fluoxetine by Other (see comment). Use Caution/Monitor. Comment: Defibrotide may enhance effects of platelet inhibitors.

            • degarelix

              degarelix and fluoxetine both increase QTc interval. Use Caution/Monitor.

            • desipramine

              olanzapine and desipramine both increase sedation. Use Caution/Monitor.

              desipramine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • desvenlafaxine

              desvenlafaxine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Desvenlafaxine inhibits CYP2D6; with higher desvenlafaxine doses (ie, 400 mg) decrease the CYP2D6 substrate dose by up to 50%; no dosage adjustment needed with desvenlafaxine doses <100 mg

            • deutetrabenazine

              olanzapine and deutetrabenazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Modify Therapy/Monitor Closely. The risk for parkinsonism, neuroleptic malignant syndrome, and akathisia may be increased by concomitant use of deutetrabenazine and dopamine antagonists or antipsychotics.

              olanzapine and deutetrabenazine both increase sedation. Use Caution/Monitor.

              deutetrabenazine and olanzapine both increase QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • deutetrabenazine

              fluoxetine will increase the level or effect of deutetrabenazine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Strong CYP2D6 inhibitors increase the systemic exposure to the active dihydro-metabolites of deutetrabenazine by approximately 3-fold. Do not exceed 18 mg/dose and 36 mg/day of deutetrabenazine if coadministered with strong CYP2D6 inhibitors.

              deutetrabenazine and fluoxetine both increase QTc interval. Use Caution/Monitor.

            • dexchlorpheniramine

              dexchlorpheniramine and olanzapine both increase sedation. Use Caution/Monitor.

            • dexfenfluramine

              fluoxetine will increase the level or effect of dexfenfluramine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

              fluoxetine and dexfenfluramine both increase serotonin levels. Modify Therapy/Monitor Closely.

              olanzapine increases and dexfenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • dexmedetomidine

              dexmedetomidine and olanzapine both increase sedation. Use Caution/Monitor.

            • dextroamphetamine

              fluoxetine will increase the level or effect of dextroamphetamine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

              fluoxetine and dextroamphetamine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • dexmethylphenidate

              olanzapine increases and dexmethylphenidate decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • dextroamphetamine

              olanzapine increases and dextroamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • dextromethorphan

              dextromethorphan, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • dextromoramide

              dextromoramide and olanzapine both increase sedation. Use Caution/Monitor.

            • diamorphine

              diamorphine and olanzapine both increase sedation. Use Caution/Monitor.

            • diazepam

              fluoxetine will increase the level or effect of diazepam by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

              diazepam and olanzapine both increase sedation. Use Caution/Monitor.

            • diazepam intranasal

              fluoxetine will increase the level or effect of diazepam intranasal by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor. Strong or moderate CYP2C19 inhibitors may decrease rate of diazepam elimination, thereby increasing adverse reactions to diazepam.

              diazepam intranasal, fluoxetine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration may potentiate the CNS-depressant effects of each drug.

            • dicyclomine

              dicyclomine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              dicyclomine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of dicyclomine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • dichlorphenamide

              dichlorphenamide and fluoxetine both decrease serum potassium. Use Caution/Monitor.

            • diclofenac

              fluoxetine will increase the level or effect of diclofenac by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

              fluoxetine, diclofenac. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • diethylpropion

              olanzapine increases and diethylpropion decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • difenoxin hcl

              difenoxin hcl and olanzapine both increase sedation. Use Caution/Monitor.

            • diflunisal

              fluoxetine, diflunisal. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • dihydroergotamine

              dihydroergotamine, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

              fluoxetine and dihydroergotamine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • dihydroergotamine intranasal

              fluoxetine and dihydroergotamine intranasal both increase serotonin levels. Modify Therapy/Monitor Closely.

            • dimenhydrinate

              dimenhydrinate and olanzapine both increase sedation. Use Caution/Monitor.

            • diphenhydramine

              diphenhydramine and olanzapine both increase sedation. Use Caution/Monitor.

              diphenhydramine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              diphenhydramine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • diphenoxylate hcl

              diphenoxylate hcl and olanzapine both increase sedation. Use Caution/Monitor.

            • dipipanone

              dipipanone and olanzapine both increase sedation. Use Caution/Monitor.

            • dobutamine

              olanzapine increases and dobutamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • dofetilide

              dofetilide increases toxicity of olanzapine by QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances.

              dofetilide and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • dolasetron

              dolasetron and fluoxetine both increase QTc interval. Use Caution/Monitor.

              dolasetron and olanzapine both increase QTc interval. Use Caution/Monitor.

            • donepezil

              donepezil and olanzapine both increase QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

              fluoxetine will increase the level or effect of donepezil by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

              donepezil and fluoxetine both increase QTc interval. Use Caution/Monitor.

            • dopamine

              olanzapine increases and dopamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • doxepin

              doxepin and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • dopexamine

              olanzapine increases and dopexamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • dosulepin

              olanzapine and dosulepin both increase sedation. Use Caution/Monitor.

            • doxepin

              olanzapine and doxepin both increase sedation. Use Caution/Monitor.

            • doxylamine

              doxylamine and olanzapine both increase sedation. Use Caution/Monitor.

            • dronedarone

              dronedarone and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • droperidol

              droperidol and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

              droperidol and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              droperidol and olanzapine both increase sedation. Use Caution/Monitor.

            • edoxaban

              fluoxetine increases effects of edoxaban by anticoagulation. Use Caution/Monitor. SSRIs may inhibit platelet aggregation, thus increase bleeding risk when coadministered with anticoagulants.

            • eletriptan

              eletriptan, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • eletriptan

              eletriptan and fluoxetine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • eliglustat

              eliglustat increases levels of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Monitor therapeutic drug concentrations, as indicated, or consider reducing the dosage of the concomitant drug and titrate to clinical effect.

            • eluxadoline

              fluoxetine increases levels of eluxadoline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. As a precautionary measure due to incomplete information on the metabolism of eluxadoline, use caution when coadministered with strong CYP2D6 inhibitors.

            • elvitegravir/cobicistat/emtricitabine/tenofovir DF

              elvitegravir/cobicistat/emtricitabine/tenofovir DF increases levels of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Cobicistat is a CYP2D6 inhibitor; caution with CYP2D6 substrates for which elevated plasma concentrations are associated with serious and/or life-threatening events.

              elvitegravir/cobicistat/emtricitabine/tenofovir DF decreases levels of fluoxetine by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. Elvitegravir is a moderate CYP2C9 inducer.

            • encainide

              fluoxetine will increase the level or effect of encainide by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

            • ephedrine

              olanzapine increases and ephedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • epinephrine

              olanzapine increases and epinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

              epinephrine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • epinephrine racemic

              olanzapine increases and epinephrine racemic decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

              epinephrine racemic and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • ergoloid mesylates

              ergoloid mesylates, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • ergotamine

              fluoxetine and ergotamine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • ergotamine

              ergotamine, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • erythromycin base

              erythromycin base and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

              erythromycin base will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • erythromycin ethylsuccinate

              erythromycin ethylsuccinate and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

              erythromycin ethylsuccinate will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • erythromycin lactobionate

              erythromycin lactobionate and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

              erythromycin lactobionate will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • erythromycin stearate

              erythromycin stearate will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

              erythromycin stearate and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • escitalopram

              escitalopram increases toxicity of olanzapine by QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances.

              escitalopram and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • esketamine intranasal

              esketamine intranasal, olanzapine. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely.

            • ethotoin

              fluoxetine will increase the level or effect of ethotoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

            • estazolam

              estazolam and olanzapine both increase sedation. Use Caution/Monitor.

            • ethanol

              olanzapine and ethanol both increase sedation. Use Caution/Monitor.

            • ethinylestradiol

              ethinylestradiol will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • etodolac

              fluoxetine, etodolac. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • etravirine

              fluoxetine will increase the level or effect of etravirine by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

            • exenatide injectable solution

              olanzapine, exenatide injectable solution. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • exenatide injectable suspension

              olanzapine, exenatide injectable suspension. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • ezogabine

              ezogabine and fluoxetine both increase QTc interval. Use Caution/Monitor. Slight and transient QT-prolongation observed with ezogabine, particularly when dose titrated to 1200 mg/day. QT interval should be monitored when ezogabine is prescribed with agents known to increase QT interval.

            • fedratinib

              fedratinib will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP2D6 substrates as necessary.

            • fenbufen

              fluoxetine, fenbufen. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • fenfluramine

              olanzapine decreases effects of fenfluramine by pharmacodynamic antagonism. Use Caution/Monitor. Potent serotonin receptor antagonists may decrease fenfluramine efficacy. If coadministered, monitor appropriately.

              fenfluramine, fluoxetine. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Coadministration with drugs that increase serotoninergic effects may increase the risk of serotonin syndrome.

              olanzapine increases and fenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

              fluoxetine and fenfluramine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • fenoprofen

              fluoxetine, fenoprofen. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • fentanyl

              fentanyl, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • fesoterodine

              fesoterodine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              fesoterodine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              fluoxetine will increase the level or effect of fesoterodine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

              olanzapine increases effects of fesoterodine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • fexinidazole

              fexinidazole will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • finerenone

              fluoxetine will increase the level or effect of finerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor serum potassium during initiation and dosage adjustment of either finererone or weak CYP3A4 inhibitors. Adjust finererone dosage as needed.

            • finerenone

              olanzapine will increase the level or effect of finerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor serum potassium during initiation and dosage adjustment of either finererone or weak CYP3A4 inhibitors. Adjust finererone dosage as needed.

            • fish oil triglycerides

              fish oil triglycerides will increase the level or effect of fluoxetine by anticoagulation. Use Caution/Monitor. Prolonged bleeding reported in patients taking antiplatelet agents or anticoagulants and oral omega-3 fatty acids. Periodically monitor bleeding time in patients receiving fish oil triglycerides and concomitant antiplatelet agents or anticoagulants.

            • flavoxate

              flavoxate decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              flavoxate decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of flavoxate by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • flecainide

              flecainide and fluoxetine both increase QTc interval. Use Caution/Monitor.

            • flibanserin

              flibanserin, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

              olanzapine will increase the level or effect of flibanserin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Increased flibanserin adverse effects may occur if coadministered with multiple weak CYP3A4 inhibitors.

              fluoxetine will increase the level or effect of flibanserin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Increased flibanserin adverse effects may occur if coadministered with multiple weak CYP3A4 inhibitors.

            • fluconazole

              fluconazole and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • fluphenazine

              fluphenazine and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              fluphenazine and olanzapine both increase sedation. Use Caution/Monitor.

            • flurazepam

              flurazepam and olanzapine both increase sedation. Use Caution/Monitor.

            • flurbiprofen

              fluoxetine will increase the level or effect of flurbiprofen by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

              fluoxetine, flurbiprofen. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • fluvastatin

              fluoxetine will increase the level or effect of fluvastatin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

            • fondaparinux

              fluoxetine increases effects of fondaparinux by anticoagulation. Use Caution/Monitor. SSRIs may inhibit platelet aggregation, thus increase bleeding risk when coadministered with anticoagulants.

            • formoterol

              fluoxetine and formoterol both increase QTc interval. Modify Therapy/Monitor Closely. Fluoxetine prolongs the QT interval; the prescribing information for fluoxetine recommends avoiding concurrent use of other drugs that may prolong the QT interval; risk may be increased with higher doses and/or when associated with hypokalemia; drugs that prolong the QTc interval may potentiate the effects of beta2 agonists on the cardiovascular system

              olanzapine increases and formoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • foscarnet

              fluoxetine and foscarnet both increase QTc interval. Use Caution/Monitor.

            • fostemsavir

              olanzapine and fostemsavir both increase QTc interval. Use Caution/Monitor. QTc prolongation reported with higher than recommended doses of fostemsavir.

            • fosphenytoin

              fluoxetine will increase the level or effect of fosphenytoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

            • fostemsavir

              fluoxetine and fostemsavir both increase QTc interval. Use Caution/Monitor. QTc prolongation reported with higher than recommended doses of fostemsavir.

            • frovatriptan

              frovatriptan, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

              frovatriptan and fluoxetine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • gabapentin

              gabapentin, fluoxetine. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.

            • glimepiride

              olanzapine, glimepiride. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • gabapentin enacarbil

              gabapentin enacarbil, fluoxetine. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.

            • galantamine

              fluoxetine will increase the level or effect of galantamine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

            • gemifloxacin

              gemifloxacin and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • glimepiride

              fluoxetine increases effects of glimepiride by unspecified interaction mechanism. Use Caution/Monitor. Risk of hypoglycemia.

            • glipizide

              fluoxetine increases effects of glipizide by unspecified interaction mechanism. Use Caution/Monitor. Risk of hypoglycemia.

              olanzapine, glipizide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • glyburide

              fluoxetine increases effects of glyburide by unspecified interaction mechanism. Use Caution/Monitor. Risk of hypoglycemia.

              olanzapine, glyburide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • glycopyrrolate

              olanzapine increases effects of glycopyrrolate by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • green tea

              green tea, fluoxetine. Other (see comment). Use Caution/Monitor. Comment: Combination may increase risk of bleeding.

            • glycopyrrolate inhaled

              glycopyrrolate inhaled decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              glycopyrrolate inhaled decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of glycopyrrolate inhaled by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • guanfacine

              guanfacine, olanzapine. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Additive hypotensive effects; potential delirium.

            • haloperidol

              haloperidol and olanzapine both increase sedation. Use Caution/Monitor.

              haloperidol and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              fluoxetine and haloperidol both increase QTc interval. Modify Therapy/Monitor Closely.

              haloperidol and olanzapine both increase QTc interval. Use Caution/Monitor.

            • henbane

              henbane decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              henbane decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of henbane by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • hydrocodone

              hydrocodone, fluoxetine. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Coadministration of drugs that affect the serotonergic neurotransmitter system may result in serotonin syndrome. If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation and dose adjustment.

            • homatropine

              homatropine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              homatropine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of homatropine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • hydromorphone

              hydromorphone and olanzapine both increase sedation. Use Caution/Monitor.

            • hydroxyzine

              hydroxyzine and olanzapine both increase sedation. Use Caution/Monitor.

            • hyoscyamine

              hyoscyamine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              hyoscyamine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of hyoscyamine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • hyoscyamine spray

              olanzapine increases effects of hyoscyamine spray by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

              hyoscyamine spray decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              hyoscyamine spray decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

            • ibrutinib

              ibrutinib will increase the level or effect of fluoxetine by anticoagulation. Use Caution/Monitor. Ibrutinib may increase the risk of hemorrhage in patients receiving antiplatelet or anticoagulant therapies and monitor for signs of bleeding.

            • ibuprofen

              fluoxetine will increase the level or effect of ibuprofen by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

              fluoxetine, ibuprofen. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • ibuprofen IV

              fluoxetine will increase the level or effect of ibuprofen IV by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

              fluoxetine, ibuprofen IV. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • iloperidone

              iloperidone and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              fluoxetine and iloperidone both increase QTc interval. Use Caution/Monitor.

              iloperidone and olanzapine both increase sedation. Use Caution/Monitor.

            • imatinib

              imatinib will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

            • imipramine

              olanzapine and imipramine both increase sedation. Use Caution/Monitor.

            • imipramine

              imipramine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • incobotulinumtoxinA

              olanzapine increases effects of incobotulinumtoxinA by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • indacaterol, inhaled

              indacaterol, inhaled and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely. Fluoxetine prolongs the QT interval; the prescribing information for fluoxetine recommends avoiding concurrent use of other drugs that may prolong the QT interval; risk may be increased with higher doses and/or when associated with hypokalemia; drugs that prolong the QTc interval may potentiate the effects of beta2 agonists on the cardiovascular system

            • indomethacin

              fluoxetine, indomethacin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • insulin aspart

              fluoxetine increases effects of insulin aspart by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

              olanzapine, insulin aspart. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • insulin aspart protamine/insulin aspart

              fluoxetine increases effects of insulin aspart protamine/insulin aspart by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

            • insulin degludec

              olanzapine decreases effects of insulin degludec by Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; dose of antidiabetic agents may need adjustment and increased frequency of glucose monitoring may be required.

            • insulin degludec

              fluoxetine, insulin degludec. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.

              fluoxetine increases effects of insulin degludec by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

            • insulin degludec/insulin aspart

              fluoxetine, insulin degludec/insulin aspart. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.

              olanzapine decreases effects of insulin degludec/insulin aspart by Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; dose of antidiabetic agents may need adjustment and increased frequency of glucose monitoring may be required.

            • insulin detemir

              olanzapine, insulin detemir. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

              fluoxetine increases effects of insulin detemir by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

            • insulin glargine

              olanzapine, insulin glargine. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

              fluoxetine increases effects of insulin glargine by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

            • insulin glulisine

              olanzapine, insulin glulisine. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

              fluoxetine increases effects of insulin glulisine by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

            • insulin inhaled

              olanzapine decreases effects of insulin inhaled by Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; dose of antidiabetic agents may need adjustment and increased frequency of glucose monitoring may be required.

              fluoxetine, insulin inhaled. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Both drugs decrease blood glucose.

              fluoxetine increases effects of insulin inhaled by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

            • insulin isophane human/insulin regular human

              fluoxetine increases effects of insulin isophane human/insulin regular human by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

            • insulin NPH

              olanzapine, insulin NPH. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • insulin lispro

              olanzapine, insulin lispro. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • insulin lispro

              fluoxetine increases effects of insulin lispro by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

            • insulin lispro protamine/insulin lispro

              fluoxetine increases effects of insulin lispro protamine/insulin lispro by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

            • insulin NPH

              fluoxetine increases effects of insulin NPH by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

            • insulin regular human

              olanzapine, insulin regular human. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

              fluoxetine increases effects of insulin regular human by unspecified interaction mechanism. Use Caution/Monitor. Concomitant use of insulin and fluoxetine may require insulin dosage adjustment and increased glucose monitoring.

            • ipratropium

              ipratropium decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              ipratropium decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of ipratropium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • isavuconazonium sulfate

              fluoxetine will increase the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

            • isavuconazonium sulfate

              olanzapine will increase the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

            • isoniazid

              fluoxetine and isoniazid both increase serotonin levels. Modify Therapy/Monitor Closely.

              isoniazid will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • isoproterenol

              olanzapine increases and isoproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • ivacaftor

              fluoxetine increases levels of ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor when coadministered with weak CYP3A4 inhibitors .

            • ivacaftor

              olanzapine increases levels of ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor when coadministered with weak CYP3A4 inhibitors .

            • ketoconazole

              fluoxetine and ketoconazole both increase QTc interval. Modify Therapy/Monitor Closely.

            • ketoprofen

              fluoxetine, ketoprofen. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • ketorolac

              fluoxetine, ketorolac. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • ketorolac intranasal

              fluoxetine, ketorolac intranasal. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • L-tryptophan

              fluoxetine and L-tryptophan both increase serotonin levels. Modify Therapy/Monitor Closely.

            • ketotifen, ophthalmic

              olanzapine and ketotifen, ophthalmic both increase sedation. Use Caution/Monitor.

            • lamotrigine

              lamotrigine increases toxicity of fluoxetine by unspecified interaction mechanism. Modify Therapy/Monitor Closely. CNS depressants may increase the toxic effects of selective serotonin reuptake inhibitors; psychomotor impairment may be enhanced.

            • lapatinib

              fluoxetine and lapatinib both increase QTc interval. Use Caution/Monitor.

            • lasmiditan

              fluoxetine increases effects of lasmiditan by serotonin levels. Use Caution/Monitor. Coadministration may increase risk of serotonin syndrome.

              lasmiditan, olanzapine. Either increases effects of the other by sedation. Use Caution/Monitor. Coadministration of lasmiditan and other CNS depressant drugs, including alcohol have not been evaluated in clinical studies. Lasmiditan may cause sedation, as well as other cognitive and/or neuropsychiatric adverse reactions.

              lasmiditan, fluoxetine. Either increases effects of the other by sedation. Use Caution/Monitor. Coadministration of lasmiditan and other CNS depressant drugs, including alcohol have not been evaluated in clinical studies. Lasmiditan may cause sedation, as well as other cognitive and/or neuropsychiatric adverse reactions.

            • lemborexant

              lemborexant, olanzapine. Either increases effects of the other by sedation. Modify Therapy/Monitor Closely. Dosage adjustment may be necessary if lemborexant is coadministered with other CNS depressants because of potentially additive effects.

              lemborexant, fluoxetine. Either increases effects of the other by sedation. Modify Therapy/Monitor Closely. Dosage adjustment may be necessary if lemborexant is coadministered with other CNS depressants because of potentially additive effects.

              olanzapine will increase the level or effect of lemborexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Lower nightly dose of lemborexant recommended if coadministered with weak CYP3A4 inhibitors. See drug monograph for specific dosage modification.

              fluoxetine will increase the level or effect of lemborexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Lower nightly dose of lemborexant recommended if coadministered with weak CYP3A4 inhibitors. See drug monograph for specific dosage modification.

            • lenvatinib

              fluoxetine and lenvatinib both increase QTc interval. Use Caution/Monitor. Lenvatinib prescribing information recommends monitoring ECG closely when coadministered with QT prolonging drugs.

            • levalbuterol

              olanzapine increases and levalbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • levalbuterol

              fluoxetine and levalbuterol both increase QTc interval. Modify Therapy/Monitor Closely. Fluoxetine prolongs the QT interval; the prescribing information for fluoxetine recommends avoiding concurrent use of other drugs that may prolong the QT interval; risk may be increased with higher doses and/or when associated with hypokalemia; drugs that prolong the QTc interval may potentiate the effects of beta2 agonists on the cardiovascular system

            • levofloxacin

              fluoxetine and levofloxacin both increase QTc interval. Use Caution/Monitor.

            • levomilnacipran

              levomilnacipran, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • levorphanol

              levorphanol and olanzapine both increase sedation. Use Caution/Monitor.

            • linezolid

              linezolid, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • liraglutide

              olanzapine, liraglutide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • lisdexamfetamine

              olanzapine increases and lisdexamfetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

              fluoxetine, lisdexamfetamine. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Initiate with lower doses and monitor for signs and symptoms of serotonin syndrome, particularly during initiation or dosage increase. If serotonin syndrome occurs, discontinue along with concomitant serotonergic drug(s).

            • lithium

              lithium, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

              fluoxetine and lithium both increase serotonin levels. Modify Therapy/Monitor Closely.

            • lofepramine

              olanzapine and lofepramine both increase sedation. Use Caution/Monitor.

            • lofexidine

              fluoxetine will increase the level or effect of lofexidine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Concomitant use of lofexidine with strong CYP2D6 inhibitors may increase lofexidine plasma levels. Monitor for symptoms of orthostasis and bradycardia if coadministered with a CYP2D6 inhibitor. Consider lofexidine dose reduction.

              fluoxetine and lofexidine both increase QTc interval. Use Caution/Monitor. ECG monitoring is recommended.

            • lofexidine

              olanzapine and lofexidine both increase sedation. Use Caution/Monitor.

            • lomitapide

              olanzapine increases levels of lomitapide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lomitapide dose should not exceed 30 mg/day.

              fluoxetine increases levels of lomitapide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lomitapide dose should not exceed 30 mg/day.

            • loprazolam

              loprazolam and olanzapine both increase sedation. Use Caution/Monitor.

            • loratadine

              fluoxetine will increase the level or effect of loratadine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

            • lorazepam

              lorazepam and olanzapine both increase sedation. Use Caution/Monitor.

            • lorcaserin

              lorcaserin will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

              lorcaserin, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • lormetazepam

              lormetazepam and olanzapine both increase sedation. Use Caution/Monitor.

            • lornoxicam

              fluoxetine, lornoxicam. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • losartan

              fluoxetine will increase the level or effect of losartan by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. May inhibit the conversion of losartan to its active metabolite E-3174. Importance of interaction not established; monitor individual therapeutic response to determine losartan dosage.

            • loxapine

              loxapine and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              loxapine and olanzapine both increase sedation. Use Caution/Monitor.

            • loxapine inhaled

              loxapine inhaled and olanzapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              loxapine inhaled and olanzapine both increase sedation. Use Caution/Monitor.

            • lsd

              fluoxetine and lsd both increase serotonin levels. Modify Therapy/Monitor Closely.

            • lumacaftor/ivacaftor

              lumacaftor/ivacaftor, fluoxetine. affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. In vitro studies suggest that lumacaftor may induce and ivacaftor may inhibit CYP2C9 substrates. .

            • lumefantrine

              fluoxetine and lumefantrine both increase QTc interval. Modify Therapy/Monitor Closely.

            • lurasidone

              lurasidone, olanzapine. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Potential for increased CNS depressant effects when used concurrently; monitor for increased adverse effects and toxicity.

              lurasidone, fluoxetine. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Potential for increased CNS depressant effects when used concurrently; monitor for increased adverse effects and toxicity.

            • maprotiline

              maprotiline and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

              olanzapine and maprotiline both increase sedation. Use Caution/Monitor.

            • maraviroc

              maraviroc, olanzapine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of orthostatic hypotension.

            • meclofenamate

              fluoxetine, meclofenamate. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • marijuana

              olanzapine and marijuana both increase sedation. Use Caution/Monitor.

            • meclizine

              meclizine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              meclizine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of meclizine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • mefenamic acid

              fluoxetine, mefenamic acid. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • melatonin

              olanzapine and melatonin both increase sedation. Use Caution/Monitor.

            • meloxicam

              fluoxetine will increase the level or effect of meloxicam by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

              fluoxetine, meloxicam. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • meperidine

              meperidine and olanzapine both increase sedation. Use Caution/Monitor.

              meperidine, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • meprobamate

              olanzapine and meprobamate both increase sedation. Use Caution/Monitor.

            • metaproterenol

              olanzapine increases and metaproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • metaxalone

              metaxalone and olanzapine both increase sedation. Use Caution/Monitor.

            • metformin

              olanzapine, metformin. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

              fluoxetine increases effects of metformin by pharmacodynamic synergism. Use Caution/Monitor.

            • methadone

              fluoxetine and methadone both increase QTc interval. Use Caution/Monitor.

              methadone and olanzapine both increase sedation. Use Caution/Monitor.

              methadone, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • methamphetamine

              olanzapine increases and methamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • midazolam intranasal

              fluoxetine will increase the level or effect of midazolam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of mild CYP3A4 inhibitors with midazolam intranasal may cause higher midazolam systemic exposure, which may prolong sedation.

              midazolam intranasal, fluoxetine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Concomitant use of barbiturates, alcohol, or other CNS depressants may increase the risk of hypoventilation, airway obstruction, desaturation, or apnea and may contribute to profound and/or prolonged drug effect.

            • methocarbamol

              methocarbamol and olanzapine both increase sedation. Use Caution/Monitor.

            • methscopolamine

              methscopolamine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              methscopolamine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of methscopolamine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • methylenedioxymethamphetamine

              olanzapine increases and methylenedioxymethamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • methylergonovine

              methylergonovine, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • methylphenidate

              olanzapine increases toxicity of methylphenidate by pharmacodynamic antagonism. Use Caution/Monitor. Closely monitor for signs of altered clinical response to either methylphenidate or an antipsychotic when using these drugs in combination.

            • metoclopramide

              olanzapine and metoclopramide both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

            • mexiletine

              mexiletine will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • midazolam

              midazolam and olanzapine both increase sedation. Use Caution/Monitor.

            • midazolam intranasal

              olanzapine will increase the level or effect of midazolam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of mild CYP3A4 inhibitors with midazolam intranasal may cause higher midazolam systemic exposure, which may prolong sedation.

              midazolam intranasal, olanzapine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Concomitant use of barbiturates, alcohol, or other CNS depressants may increase the risk of hypoventilation, airway obstruction, desaturation, or apnea and may contribute to profound and/or prolonged drug effect.

            • midodrine

              olanzapine increases and midodrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • mifepristone

              mifepristone, fluoxetine. QTc interval. Modify Therapy/Monitor Closely. Use alternatives if available.

              mifepristone, olanzapine. QTc interval. Modify Therapy/Monitor Closely. Use alternatives if available.

            • miglitol

              olanzapine, miglitol. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • mipomersen

              mipomersen, fluoxetine. Either increases toxicity of the other by Other (see comment). Use Caution/Monitor. Comment: Both drugs have potential to increase hepatic enzymes; monitor LFTs.

            • milnacipran

              milnacipran, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • mirabegron

              mirabegron will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

            • mirtazapine

              fluoxetine and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely.

              olanzapine and mirtazapine both increase sedation. Use Caution/Monitor.

            • modafinil

              modafinil will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

              olanzapine increases and modafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • morphine

              fluoxetine and morphine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • morphine

              morphine and olanzapine both increase sedation. Use Caution/Monitor.

            • motherwort

              olanzapine and motherwort both increase sedation. Use Caution/Monitor.

            • moxifloxacin

              fluoxetine and moxifloxacin both increase QTc interval. Modify Therapy/Monitor Closely.

            • moxonidine

              olanzapine and moxonidine both increase sedation. Use Caution/Monitor.

            • nabilone

              olanzapine and nabilone both increase sedation. Use Caution/Monitor.

            • nabumetone

              fluoxetine, nabumetone. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • nalbuphine

              nalbuphine and olanzapine both increase sedation. Use Caution/Monitor.

            • naproxen

              fluoxetine, naproxen. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • naratriptan

              naratriptan and fluoxetine both increase serotonin levels. Modify Therapy/Monitor Closely.

              naratriptan, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • nateglinide

              olanzapine, nateglinide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

              fluoxetine will increase the level or effect of nateglinide by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

            • nifedipine

              fluoxetine will increase the level or effect of nifedipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Consider initiating nifedipine at the lowest dose available if given concomitantly with this medication

            • norepinephrine

              olanzapine increases and norepinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • nilotinib

              fluoxetine and nilotinib both increase QTc interval. Modify Therapy/Monitor Closely.

            • nitisinone

              nitisinone will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. Nitisinone inhibits CYP2C9. Caution if CYP2C9 substrate coadministered, particularly those with a narrow therapeutic index.

            • nortriptyline

              olanzapine and nortriptyline both increase sedation. Use Caution/Monitor.

              nortriptyline and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • octreotide

              fluoxetine and octreotide both increase QTc interval. Modify Therapy/Monitor Closely.

            • oliceridine

              oliceridine, olanzapine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Profound sedation, respiratory depression, coma, and death may result if coadministered. Reserve concomitant prescribing of these drugs in patients for whom other treatment options are inadequate. Limit dosages and durations to the minimum required. Monitor closely for signs of respiratory depression and sedation.

            • octreotide (Antidote)

              fluoxetine and octreotide (Antidote) both increase QTc interval. Modify Therapy/Monitor Closely.

            • ofloxacin

              fluoxetine and ofloxacin both increase QTc interval. Use Caution/Monitor.

            • oliceridine

              fluoxetine will increase the level or effect of oliceridine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. If concomitant use is necessary, may require less frequent oliceridine dosing. Closely monitor for respiratory depression and sedation and titrate subsequent doses accordingly. If inhibitor is discontinued, consider increase oliceridine dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal.

              fluoxetine, oliceridine. Either increases toxicity of the other by serotonin levels. Modify Therapy/Monitor Closely.

            • olodaterol inhaled

              fluoxetine and olodaterol inhaled both increase QTc interval. Modify Therapy/Monitor Closely. Fluoxetine prolongs the QT interval; the prescribing information for fluoxetine recommends avoiding concurrent use of other drugs that may prolong the QT interval; risk may be increased with higher doses and/or when associated with hypokalemia; drugs that prolong the QTc interval may potentiate the effects of beta2 agonists on the cardiovascular system

            • onabotulinumtoxinA

              onabotulinumtoxinA decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              onabotulinumtoxinA decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of onabotulinumtoxinA by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • opium tincture

              opium tincture and olanzapine both increase sedation. Use Caution/Monitor.

            • orphenadrine

              orphenadrine and olanzapine both increase sedation. Use Caution/Monitor.

            • osilodrostat

              osilodrostat and olanzapine both increase QTc interval. Use Caution/Monitor.

              osilodrostat and fluoxetine both increase QTc interval. Use Caution/Monitor.

            • osimertinib

              osimertinib and olanzapine both increase QTc interval. Use Caution/Monitor. Conduct periodic monitoring with ECGs and electrolytes in patients taking drugs known to prolong the QTc interval.

              osimertinib and fluoxetine both increase QTc interval. Use Caution/Monitor. Conduct periodic monitoring with ECGs and electrolytes in patients taking drugs known to prolong the QTc interval.

            • oxaliplatin

              oxaliplatin will increase the level or effect of olanzapine by Other (see comment). Use Caution/Monitor. Monitor for ECG changes if therapy is initiated in patients with drugs known to prolong QT interval.

            • oxaprozin

              fluoxetine, oxaprozin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • oxazepam

              oxazepam and olanzapine both increase sedation. Use Caution/Monitor.

            • oxybutynin

              oxybutynin decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              oxybutynin decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of oxybutynin by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • oxybutynin topical

              oxybutynin topical decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              oxybutynin topical decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of oxybutynin topical by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • oxybutynin transdermal

              oxybutynin transdermal decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              oxybutynin transdermal decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of oxybutynin transdermal by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • oxycodone

              oxycodone and olanzapine both increase sedation. Use Caution/Monitor.

            • oxymorphone

              oxymorphone and olanzapine both increase sedation. Use Caution/Monitor.

            • ozanimod

              ozanimod and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely. The potential additive effects on heart rate, treatment with ozanimod should generally not be initiated in patients who are concurrently treated with QT prolonging drugs with known arrhythmogenic properties.

              ozanimod and olanzapine both increase QTc interval. Modify Therapy/Monitor Closely. The potential additive effects on heart rate, treatment with ozanimod should generally not be initiated in patients who are concurrently treated with QT prolonging drugs with known arrhythmogenic properties.

            • paliperidone

              olanzapine and paliperidone both increase sedation. Use Caution/Monitor.

              fluoxetine and paliperidone both increase QTc interval. Use Caution/Monitor.

              olanzapine and paliperidone both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

            • pancuronium

              pancuronium decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              pancuronium decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of pancuronium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • parecoxib

              fluoxetine will increase the level or effect of parecoxib by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

              fluoxetine, parecoxib. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • papaveretum

              papaveretum and olanzapine both increase sedation. Use Caution/Monitor.

            • papaverine

              olanzapine and papaverine both increase sedation. Use Caution/Monitor.

            • paroxetine

              paroxetine, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

              fluoxetine and paroxetine both increase QTc interval. Use Caution/Monitor.

            • pasireotide

              olanzapine and pasireotide both increase QTc interval. Modify Therapy/Monitor Closely.

              fluoxetine and pasireotide both increase QTc interval. Modify Therapy/Monitor Closely.

            • peginterferon alfa 2a

              peginterferon alfa 2a will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • peginterferon alfa 2b

              peginterferon alfa 2b, fluoxetine. Other (see comment). Use Caution/Monitor. Comment: When patients are administered peginterferon alpha-2b with CYP2D6 substrates, the therapeutic effect of these drugs may be altered. Peginterferon alpha-2b may increase or decrease levels of CYP2D6 substrate.

            • pentazocine

              pentazocine and olanzapine both increase sedation. Use Caution/Monitor.

              fluoxetine and pentazocine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • pentobarbital

              pentobarbital will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

              pentobarbital and olanzapine both increase sedation. Use Caution/Monitor.

            • pentoxifylline

              pentoxifylline increases toxicity of fluoxetine by anticoagulation. Use Caution/Monitor. May increase bleeding.

            • perhexiline

              fluoxetine will increase the level or effect of perhexiline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

            • perphenazine

              olanzapine and perphenazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              olanzapine and perphenazine both increase sedation. Use Caution/Monitor.

            • phendimetrazine

              olanzapine increases and phendimetrazine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • phenelzine

              phenelzine, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • phenobarbital

              phenobarbital will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

              phenobarbital and olanzapine both increase sedation. Use Caution/Monitor.

            • phentermine

              olanzapine increases and phentermine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • phenylephrine

              olanzapine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • phenylephrine PO

              olanzapine increases and phenylephrine PO decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. .

            • phenytoin

              fluoxetine will increase the level or effect of phenytoin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

            • pholcodine

              olanzapine and pholcodine both increase sedation. Use Caution/Monitor.

            • pimozide

              olanzapine and pimozide both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              olanzapine and pimozide both increase sedation. Use Caution/Monitor.

            • pioglitazone

              olanzapine, pioglitazone. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • pipemidic acid

              pipemidic acid will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • pirbuterol

              olanzapine increases and pirbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

              fluoxetine and pirbuterol both increase QTc interval. Modify Therapy/Monitor Closely. Fluoxetine prolongs the QT interval; the prescribing information for fluoxetine recommends avoiding concurrent use of other drugs that may prolong the QT interval; risk may be increased with higher doses and/or when associated with hypokalemia; drugs that prolong the QTc interval may potentiate the effects of beta2 agonists on the cardiovascular system

            • piroxicam

              fluoxetine will increase the level or effect of piroxicam by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

              fluoxetine, piroxicam. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • pralidoxime

              pralidoxime decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              pralidoxime decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of pralidoxime by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • pitolisant

              fluoxetine will increase the level or effect of pitolisant by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. If coadministered with strong CYP2D6 inhibitors, initiate pitolisant at 8.9 mg/day and increase after 7 days to maximum of 17.8 mg/day. For patients currently taking pitolisant, reduce pitolisant dose by half upon initiating strong CYP2D6 inhibitors.

            • posaconazole

              fluoxetine and posaconazole both increase QTc interval. Use Caution/Monitor.

            • pramlintide

              olanzapine, pramlintide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • pregabalin

              pregabalin, fluoxetine. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of CNS depressants can result in serious, life-threatening, and fatal respiratory depression. Use lowest dose possible and monitor for respiratory depression and sedation.

            • primidone

              primidone will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

              primidone and olanzapine both increase sedation. Use Caution/Monitor.

            • procarbazine

              procarbazine, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • prochlorperazine

              olanzapine and prochlorperazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              fluoxetine will increase the level or effect of prochlorperazine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

              olanzapine and prochlorperazine both increase sedation. Use Caution/Monitor.

              prochlorperazine and fluoxetine both increase QTc interval. Use Caution/Monitor.

            • promazine

              fluoxetine will increase the level or effect of promazine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

              promazine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • promethazine

              olanzapine and promethazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              promethazine and olanzapine both increase sedation. Use Caution/Monitor.

              promethazine, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • promethazine

              promethazine and fluoxetine both increase QTc interval. Use Caution/Monitor.

            • propantheline

              propantheline decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              propantheline decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of propantheline by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • propofol

              propofol and olanzapine both increase sedation. Use Caution/Monitor.

            • propylhexedrine

              olanzapine increases and propylhexedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • protriptyline

              olanzapine and protriptyline both increase sedation. Use Caution/Monitor.

              protriptyline and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • quazepam

              quazepam and olanzapine both increase sedation. Use Caution/Monitor.

            • quetiapine

              quetiapine, fluoxetine. Either increases toxicity of the other by QTc interval. Use Caution/Monitor. Avoid use with drugs that prolong QT and in patients with risk factors for prolonged QT interval. Postmarketing cases show QT prolongation with overdose in patients with concomitant illness or with drugs known to cause electrolyte imbalance or prolong QT.

            • quetiapine

              olanzapine and quetiapine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              olanzapine and quetiapine both increase sedation. Use Caution/Monitor.

            • quinine

              fluoxetine and quinine both increase QTc interval. Use Caution/Monitor.

              olanzapine and quinine both increase QTc interval. Use Caution/Monitor.

            • ramelteon

              fluoxetine will increase the level or effect of ramelteon by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

              olanzapine and ramelteon both increase sedation. Use Caution/Monitor.

            • ranolazine

              fluoxetine and ranolazine both increase QTc interval. Use Caution/Monitor.

            • rapacuronium

              rapacuronium decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              rapacuronium decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of rapacuronium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • remifentanil

              remifentanil, fluoxetine. Either increases toxicity of the other by serotonin levels. Modify Therapy/Monitor Closely.

            • remimazolam

              remimazolam, fluoxetine. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely. Coadministration may result in profound sedation, respiratory depression, coma, and/or death. Continuously monitor vital signs during sedation and recovery period if coadministered. Carefully titrate remimazolam dose if administered with opioid analgesics and/or sedative/hypnotics.

              remimazolam, olanzapine. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely. Coadministration may result in profound sedation, respiratory depression, coma, and/or death. Continuously monitor vital signs during sedation and recovery period if coadministered. Carefully titrate remimazolam dose if administered with opioid analgesics and/or sedative/hypnotics.

            • repaglinide

              olanzapine, repaglinide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • rilpivirine

              rilpivirine increases toxicity of fluoxetine by QTc interval. Use Caution/Monitor. Rilpivirine should be used with caution when co-administered with a drug with a known risk of Torsades de Pointes.

            • rifampin

              rifampin will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • rimabotulinumtoxinB

              olanzapine, rimabotulinumtoxinB. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Anticholinergics may enhance botulinum toxin effects. Closely monitor for increased neuromuscular blockade.

            • risperidone

              olanzapine and risperidone both increase sedation. Use Caution/Monitor.

              fluoxetine and risperidone both increase QTc interval. Use Caution/Monitor.

              olanzapine and risperidone both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

            • ritonavir

              ritonavir decreases levels of olanzapine by increasing metabolism. Use Caution/Monitor.

            • rivaroxaban

              fluoxetine increases effects of rivaroxaban by pharmacodynamic synergism. Use Caution/Monitor. Combination may increase risk of bleeding.

            • rizatriptan

              rizatriptan and fluoxetine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • rocuronium

              rocuronium decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              rocuronium decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of rocuronium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • rolapitant

              rolapitant will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Rolapitant may increase plasma concentrations of CYP2D6 substrates for at least 28 days following rolapitant administration.

            • romidepsin

              fluoxetine and romidepsin both increase QTc interval. Use Caution/Monitor.

            • rosiglitazone

              olanzapine, rosiglitazone. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • rucaparib

              rucaparib will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP1A2 substrates, if clinically indicated.

              rucaparib will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2C9/10 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP2C9 substrates, if clinically indicated.

            • safinamide

              fluoxetine, safinamide. Either increases toxicity of the other by serotonin levels. Use Caution/Monitor. Monitor patients for symptoms of serotonin syndrome if SSRIs are coadministered with safinamide.

            • salmeterol

              olanzapine increases and salmeterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • salicylates (non-asa)

              fluoxetine, salicylates (non-asa). Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • salmeterol

              fluoxetine and salmeterol both increase QTc interval. Modify Therapy/Monitor Closely. Fluoxetine prolongs the QT interval; the prescribing information for fluoxetine recommends avoiding concurrent use of other drugs that may prolong the QT interval; risk may be increased with higher doses and/or when associated with hypokalemia; drugs that prolong the QTc interval may potentiate the effects of beta2 agonists on the cardiovascular system

            • salsalate

              fluoxetine, salsalate. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • SAMe

              fluoxetine and SAMe both increase serotonin levels. Modify Therapy/Monitor Closely.

            • saquinavir

              saquinavir and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • saxagliptin

              olanzapine, saxagliptin. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • scopolamine

              scopolamine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              scopolamine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of scopolamine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • scullcap

              olanzapine and scullcap both increase sedation. Use Caution/Monitor.

            • secobarbital

              secobarbital will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

              secobarbital and olanzapine both increase sedation. Use Caution/Monitor.

            • selegiline

              selegiline, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • selpercatinib

              selpercatinib increases toxicity of olanzapine by QTc interval. Use Caution/Monitor.

              selpercatinib increases toxicity of fluoxetine by QTc interval. Use Caution/Monitor.

            • sertraline

              sertraline and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • shepherd's purse

              olanzapine and shepherd's purse both increase sedation. Use Caution/Monitor.

            • sitagliptin

              olanzapine, sitagliptin. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • smoking

              smoking will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • sodium sulfate/?magnesium sulfate/potassium chloride

              sodium sulfate/?magnesium sulfate/potassium chloride increases effects of olanzapine by unknown mechanism. Use Caution/Monitor. Closely monitor for evidence of enhanced CNS depression when using higher dose of magnesium sulfate together with a CNS depressant.

              sodium sulfate/?magnesium sulfate/potassium chloride increases effects of fluoxetine by unknown mechanism. Use Caution/Monitor. Closely monitor for evidence of seizures when using bowel preps together with drugs that lower the seizure threshold.

            • sodium sulfate/potassium sulfate/magnesium sulfate

              sodium sulfate/potassium sulfate/magnesium sulfate increases effects of fluoxetine by unknown mechanism. Use Caution/Monitor. Closely monitor for evidence of seizures when using bowel preps together with drugs that lower the seizure threshold.

              sodium sulfate/potassium sulfate/magnesium sulfate increases effects of olanzapine by unknown mechanism. Use Caution/Monitor. Closely monitor for evidence of enhanced CNS depression when using higher dose of magnesium sulfate together with a CNS depressant.

            • sodium sulfate/potassium sulfate/magnesium sulfate/polyethylene glycol

              fluoxetine, sodium sulfate/potassium sulfate/magnesium sulfate/polyethylene glycol. Other (see comment). Use Caution/Monitor. Comment: Caution when bowel preps are used with drugs that cause SIADH or NSAIDs; increased risk for water retention or electrolyte imbalance.

            • solifenacin

              solifenacin decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              solifenacin decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of solifenacin by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • sorafenib

              sorafenib and fluoxetine both increase QTc interval. Use Caution/Monitor.

              sorafenib and olanzapine both increase QTc interval. Use Caution/Monitor. Limited data, including some case reports, suggest that olanzapine may be associated with a significant prolongation of the QTc interval in rare instances

            • stiripentol

              stiripentol, olanzapine. affecting hepatic enzyme CYP1A2 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP1A2 inhibitor and inducer. Monitor CYP1A2 substrates coadministered with stiripentol for increased or decreased effects. CYP1A2 substrates may require dosage adjustment.

              stiripentol, olanzapine. Either increases effects of the other by sedation. Use Caution/Monitor. Concomitant use stiripentol with other CNS depressants, including alcohol, may increase the risk of sedation and somnolence.

            • sufentanil SL

              sufentanil SL, fluoxetine. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Coadministration of drugs that affect the serotonergic neurotransmitter system may result in serotonin syndrome. If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation and dose adjustment.

            • sufentanil

              sufentanil and olanzapine both increase sedation. Use Caution/Monitor.

            • sulfamethoxazole

              fluoxetine will increase the level or effect of sulfamethoxazole by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

            • sulfasalazine

              fluoxetine, sulfasalazine. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • sulindac

              fluoxetine, sulindac. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • sumatriptan

              sumatriptan, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

              sumatriptan and fluoxetine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • sumatriptan intranasal

              sumatriptan intranasal, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

              sumatriptan intranasal and fluoxetine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • sunitinib

              sunitinib and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • tapentadol

              tapentadol and olanzapine both increase sedation. Use Caution/Monitor.

            • tamoxifen

              fluoxetine will decrease the level or effect of tamoxifen by decreasing metabolism. Use Caution/Monitor. Inhibition of CYP2D6 metabolism to tamoxifen's active metabolite, endoxifen.

            • tamsulosin

              fluoxetine increases levels of tamsulosin by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

            • tapentadol

              fluoxetine and tapentadol both increase serotonin levels. Modify Therapy/Monitor Closely.

            • tazemetostat

              olanzapine will increase the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

              fluoxetine will increase the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

            • telavancin

              fluoxetine and telavancin both increase QTc interval. Use Caution/Monitor.

            • temazepam

              temazepam and olanzapine both increase sedation. Use Caution/Monitor.

            • terbinafine

              terbinafine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Assess need to reduce dose of CYP2D6-metabolized drug.

            • terbutaline

              fluoxetine and terbutaline both increase QTc interval. Modify Therapy/Monitor Closely. Fluoxetine prolongs the QT interval; the prescribing information for fluoxetine recommends avoiding concurrent use of other drugs that may prolong the QT interval; risk may be increased with higher doses and/or when associated with hypokalemia; drugs that prolong the QTc interval may potentiate the effects of beta2 agonists on the cardiovascular system

              olanzapine increases and terbutaline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • teriflunomide

              teriflunomide decreases levels of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • tetrabenazine

              fluoxetine increases effects of tetrabenazine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Decrease tetrabenazine dose by 50% when coadministered with strong CYP2D6 inhibitors.

            • tetrabenazine

              olanzapine and tetrabenazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Modify Therapy/Monitor Closely.

            • thioridazine

              olanzapine and thioridazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              olanzapine and thioridazine both increase sedation. Use Caution/Monitor.

            • thiothixene

              olanzapine and thiothixene both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              thiothixene and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

              olanzapine and thiothixene both increase sedation. Use Caution/Monitor.

            • tinidazole

              fluoxetine will increase the level or effect of tinidazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

              olanzapine will increase the level or effect of tinidazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

            • tiotropium

              tiotropium decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              tiotropium decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of tiotropium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • tolazamide

              fluoxetine increases effects of tolazamide by unspecified interaction mechanism. Use Caution/Monitor. Risk of hypoglycemia.

            • tobacco use

              tobacco use will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • tolazamide

              olanzapine, tolazamide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • tolbutamide

              fluoxetine increases effects of tolbutamide by unspecified interaction mechanism. Use Caution/Monitor. Risk of hypoglycemia.

              fluoxetine will increase the level or effect of tolbutamide by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

              olanzapine, tolbutamide. Other (see comment). Use Caution/Monitor. Comment: Atypical antipsychotics have been associated with hyperglycemia that may alter blood glucose control; monitor glucose levels closely.

            • tolfenamic acid

              fluoxetine, tolfenamic acid. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • tolterodine

              tolterodine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              tolterodine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of tolterodine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • tolmetin

              fluoxetine, tolmetin. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of upper GI bleeding. SSRIs inhib. serotonin uptake by platelets.

            • topiramate

              olanzapine and topiramate both increase sedation. Modify Therapy/Monitor Closely.

            • toremifene

              toremifene and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • tramadol

              tramadol and olanzapine both increase sedation. Use Caution/Monitor.

              fluoxetine and tramadol both increase serotonin levels. Modify Therapy/Monitor Closely.

            • tranylcypromine

              tranylcypromine, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • trazodone

              trazodone and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • trazodone

              olanzapine and trazodone both increase sedation. Use Caution/Monitor.

            • triazolam

              triazolam and olanzapine both increase sedation. Use Caution/Monitor.

            • triclabendazole

              triclabendazole and olanzapine both increase QTc interval. Use Caution/Monitor.

              triclabendazole and fluoxetine both increase QTc interval. Use Caution/Monitor.

            • triclofos

              triclofos and olanzapine both increase sedation. Use Caution/Monitor.

            • trifluoperazine

              fluoxetine will increase the level or effect of trifluoperazine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

              trifluoperazine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • trifluoperazine

              olanzapine and trifluoperazine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              olanzapine and trifluoperazine both increase sedation. Use Caution/Monitor.

            • trihexyphenidyl

              olanzapine increases effects of trihexyphenidyl by pharmacodynamic synergism. Use Caution/Monitor. Potential for additive anticholinergic effects.

            • trimethoprim

              fluoxetine and trimethoprim both increase QTc interval. Use Caution/Monitor.

            • trimipramine

              trimipramine and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

              olanzapine and trimipramine both increase sedation. Use Caution/Monitor.

            • triprolidine

              triprolidine and olanzapine both increase sedation. Use Caution/Monitor.

            • tropisetron

              fluoxetine will increase the level or effect of tropisetron by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

              fluoxetine and tropisetron both increase QTc interval. Use Caution/Monitor.

            • trospium chloride

              trospium chloride decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              trospium chloride decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of trospium chloride by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • umeclidinium bromide/vilanterol inhaled

              fluoxetine and umeclidinium bromide/vilanterol inhaled both increase QTc interval. Modify Therapy/Monitor Closely. Fluoxetine prolongs the QT interval; the prescribing information for fluoxetine recommends avoiding concurrent use of other drugs that may prolong the QT interval; risk may be increased with higher doses and/or when associated with hypokalemia; drugs that prolong the QTc interval may potentiate the effects of beta2 agonists on the cardiovascular system

            • valbenazine

              fluoxetine will increase the level or effect of valbenazine by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Consider reducing valbenazine dose based on tolerability if coadministered with a strong CYP2D6 inhibitor.

            • valerian

              valerian and fluoxetine both increase sedation. Use Caution/Monitor.

            • vardenafil

              vardenafil and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • vecuronium

              vecuronium decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.

              vecuronium decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.

              olanzapine increases effects of vecuronium by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

            • venlafaxine

              fluoxetine and venlafaxine both increase QTc interval. Use Caution/Monitor.

              venlafaxine, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • verapamil

              verapamil will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • vilanterol/fluticasone furoate inhaled

              fluoxetine and vilanterol/fluticasone furoate inhaled both increase QTc interval. Modify Therapy/Monitor Closely. Fluoxetine prolongs the QT interval; the prescribing information for fluoxetine recommends avoiding concurrent use of other drugs that may prolong the QT interval; risk may be increased with higher doses and/or when associated with hypokalemia; drugs that prolong the QTc interval may potentiate the effects of beta2 agonists on the cardiovascular system

            • vilazodone

              vilazodone, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

            • voclosporin

              voclosporin, olanzapine. Either increases effects of the other by QTc interval. Use Caution/Monitor.

              voclosporin, fluoxetine. Either increases effects of the other by QTc interval. Use Caution/Monitor.

            • vorapaxar

              fluoxetine, vorapaxar. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Additive antiplatelet effect may occur; SSRIs and SNRIs may cause platelet serotonin depletion .

            • xylometazoline

              olanzapine increases and xylometazoline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • voriconazole

              fluoxetine will increase the level or effect of voriconazole by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

              fluoxetine and voriconazole both increase QTc interval. Use Caution/Monitor.

            • vorinostat

              vorinostat and fluoxetine both increase QTc interval. Modify Therapy/Monitor Closely.

            • warfarin

              fluoxetine will increase the level or effect of warfarin by affecting hepatic enzyme CYP2C19 metabolism. Use Caution/Monitor.

              fluoxetine will increase the level or effect of warfarin by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor.

            • yohimbine

              olanzapine increases and yohimbine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • zanubrutinib

              fluoxetine, zanubrutinib. Either increases effects of the other by anticoagulation. Modify Therapy/Monitor Closely. Zanubrutinib-induced cytopenias increases risk of hemorrhage. Coadministration of zanubritinib with antiplatelets or anticoagulants may further increase this risk.

            • ziconotide

              olanzapine and ziconotide both increase sedation. Use Caution/Monitor.

            • zileuton

              zileuton will increase the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.

            • ziprasidone

              olanzapine and ziprasidone both increase sedation. Use Caution/Monitor.

              fluoxetine and ziprasidone both increase QTc interval. Modify Therapy/Monitor Closely.

              olanzapine and ziprasidone both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

            • zolmitriptan

              zolmitriptan, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).

              zolmitriptan and fluoxetine both increase serotonin levels. Modify Therapy/Monitor Closely.

            • zotepine

              olanzapine and zotepine both increase sedation. Use Caution/Monitor.

              olanzapine and zotepine both increase antidopaminergic effects, including extrapyramidal symptoms and neuroleptic malignant syndrome. Use Caution/Monitor.

              fluoxetine increases levels of zotepine by decreasing metabolism. Use Caution/Monitor.

            Minor (41)

            • almotriptan

              fluoxetine, almotriptan. Mechanism: unknown. Minor/Significance Unknown. Risk of weakness, dyspnea, chest pain.

            • azithromycin

              azithromycin and fluoxetine both increase QTc interval. Minor/Significance Unknown.

            • brimonidine

              brimonidine increases effects of olanzapine by pharmacodynamic synergism. Minor/Significance Unknown. Increased CNS depression.

            • bumetanide

              bumetanide, fluoxetine. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Possible additive hyponatremia.

            • celandine

              celandine decreases effects of fluoxetine by pharmacodynamic antagonism. Minor/Significance Unknown. Based on animal studies.

            • chasteberry

              chasteberry decreases effects of olanzapine by pharmacodynamic antagonism. Minor/Significance Unknown. (Theoretical interaction).

            • chloroquine

              chloroquine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

              chloroquine increases toxicity of fluoxetine by QTc interval. Minor/Significance Unknown.

            • codeine

              fluoxetine decreases effects of codeine by decreasing metabolism. Minor/Significance Unknown. Decreased conversion of codeine to active metabolite morphine.

            • darifenacin

              darifenacin will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

            • dexmethylphenidate

              dexmethylphenidate increases effects of fluoxetine by decreasing metabolism. Minor/Significance Unknown.

            • diphenhydramine

              diphenhydramine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

            • dronedarone

              dronedarone will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

            • duloxetine

              duloxetine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

            • eletriptan

              fluoxetine, eletriptan. Mechanism: unknown. Minor/Significance Unknown. Risk of weakness, dyspnea, chest pain.

            • esomeprazole

              fluoxetine will increase the level or effect of esomeprazole by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

            • ethacrynic acid

              ethacrynic acid, fluoxetine. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Possible additive hyponatremia.

            • ethanol

              ethanol, olanzapine. Either increases toxicity of the other by pharmacodynamic synergism. Minor/Significance Unknown. Additive CNS depression.

            • eucalyptus

              olanzapine and eucalyptus both increase sedation. Minor/Significance Unknown.

            • frovatriptan

              fluoxetine, frovatriptan. Mechanism: unknown. Minor/Significance Unknown. Risk of weakness, dyspnea, chest pain.

            • furosemide

              furosemide, fluoxetine. Mechanism: pharmacodynamic synergism. Minor/Significance Unknown. Possible additive hyponatremia.

            • lansoprazole

              fluoxetine will increase the level or effect of lansoprazole by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

            • lithium

              fluoxetine, lithium. Mechanism: unknown. Minor/Significance Unknown. Risk of neurotoxicity.

            • losartan

              fluoxetine decreases effects of losartan by decreasing metabolism. Minor/Significance Unknown. May inhibit the conversion of losartan to its active metabolite E-3174. Importance of interaction not established; monitor individual therapeutic response to determine losartan dosage.

            • maraviroc

              maraviroc will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

            • marijuana

              marijuana will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

            • naratriptan

              fluoxetine, naratriptan. Mechanism: unknown. Minor/Significance Unknown. Risk of weakness, dyspnea, chest pain.

            • nilotinib

              nilotinib will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

            • omeprazole

              omeprazole will decrease the level or effect of olanzapine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.

              fluoxetine will increase the level or effect of omeprazole by affecting hepatic enzyme CYP2C9/10 metabolism. Minor/Significance Unknown.

            • panax ginseng

              panax ginseng increases effects of fluoxetine by pharmacodynamic synergism. Minor/Significance Unknown.

            • ruxolitinib

              olanzapine will increase the level or effect of ruxolitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

            • parecoxib

              parecoxib will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

            • pazopanib

              fluoxetine and pazopanib both increase QTc interval. Minor/Significance Unknown.

            • pleurisy root

              pleurisy root decreases effects of fluoxetine by unspecified interaction mechanism. Minor/Significance Unknown. Theoretical interaction.

            • quinacrine

              quinacrine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

            • rabeprazole

              fluoxetine will increase the level or effect of rabeprazole by affecting hepatic enzyme CYP2C19 metabolism. Minor/Significance Unknown.

            • ranolazine

              ranolazine will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

            • ritonavir

              ritonavir will increase the level or effect of fluoxetine by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.

            • rizatriptan

              fluoxetine, rizatriptan. Mechanism: unknown. Minor/Significance Unknown. Risk of weakness, dyspnea, chest pain.

            • ruxolitinib

              fluoxetine will increase the level or effect of ruxolitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.

            • sage

              olanzapine and sage both increase sedation. Minor/Significance Unknown.

            • sumatriptan

              fluoxetine, sumatriptan. Mechanism: unknown. Minor/Significance Unknown. Risk of weakness, dyspnea, chest pain.

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            Adverse Effects

            Frequency Not Defined

            Rhabdomyolysis and venous thromboembolic events (including pulmonary embolism and deep venous thrombosis)

            Fluoxetine

            • Aplastic anemia, cholestatic jaundice, eosinophilic pneumonia, erythema multiforme, violent behavior, atrial fibrillation, cataract, cerebrovascular accident, epidermal necrolysis, erythema nodosum, heart arrest, hepatic failure/necrosis, hypoglycemia, kidney failure, memory impairment, optic neuritis, pulmonary hypertension, Stevens-Johnson syndrome.

            Olanzapine

            • Diabetic coma, jaundice, random triglyceride levels of greater than or equal to 1000 mg/dL, restless legs syndrome, stuttering, salivary hypersecretion, allergic reaction (eg, anaphylactoid reaction, angioedema, pruritus or urticaria), diabetic ketoacidosis, discontinuation reaction (diaphoresis, nausea or vomiting), drug reaction with eosinophilia and systemic symptoms (DRESS)
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            Warnings

            Black Box Warnings

            Children and antidepressants

            • In short-term studies, antidepressants increased the risk of suicidal thinking and behavior in children, adolescents, and young adults (<24 years of age) taking antidepressants for major depressive disorders and other psychiatric illnesses
            • This increase was not seen in patients >24 years of age
            • A slight decrease in suicidal thinking was seen in adults >65 years
            • Risks must be weighed in children and young adults against the benefits of taking antidepressants
            • Patients should be monitored closely for changes in behavior, clinical worsening, and suicidal tendencies; this should be done during the initial 1-2 months of therapy and dosage adjustments
            • The patient’s family should communicate to the healthcare provider any abrupt changes in behavior; worsening behavior and suicidal tendencies that are not part of the presenting symptoms may require discontinuation of therapy
            • This drug is not approved for use in pediatric patients

            Antipsychotics & Dementia

            • Patients with dementia-related psychosis that are treated with antipsychotic drugs are at an increased risk of death as shown in short-term controlled trials
            • The deaths appeared to be either cardiovascular (eg, heart failure, sudden death) or infectious (eg, pneumonia) in nature
            • This drug is not approved for the treatment of patients with dementia-related psychosis (See WARNINGS in package insert)

            Contraindications

            Hypersensitivity to any component

            Concomitant thioridazine, pimozide

            Coadministration with MAOIs

            • Coadministration may cause serotonin syndrome
            • Increased risk when MAOIs coadministered with fluoxetine or within 5 weeks of discontinuing fluoxetine/olanzapine
            • Serotonin syndrome symptoms include tremor, myoclonus, diaphoresis, nausea, vomiting, flushing, dizziness, hyperthermia with features resembling neuroleptic malignant syndrome, seizures, rigidity, autonomic instability with possible rapid fluctuations of vital signs, and mental status changes that include extreme agitation progressing to delirium and coma
            • Starting fluoxetine in a patient who is being treated with linezolid or IV methylene blue is contraindicated because of an increased risk of serotonin syndrome
            • See Dosing Considerations and Dosage Modifications

            Cautions

            Hypertension, hepatic impairment, slow metabolizers

            Conflicting evidence regarding use of SSRIs during pregnancy and increased risk of persistent pulmonary hypertension of the newborn (see Pregnancy)

            Pupillary dilation occurs following use of many antidepressant drugs may trigger an angle-closure attack in a patient with anatomically narrow angles who does not have a patent iridectomy

            Anaphylactoid reactions (eg, bronchospasm, angioedema, and urticaria) alone and in combination, reported

            Avoid alcohol

            Prescribe the smallest quantity consistent with good patient care

            Risk of orthostatic hypotension

            Use with caution in patients with current diagnosis or prior history of urinary retention

            Potential for abnormal bleeding with concomitant ASA, NSAIDs, or other antiplatelet drugs

            Risk of mydriasis; may trigger angle closure attack in patients with angle closure glaucoma with anatomically narrow angles without a patent iridectomy

            Neonates exposed to SNRIs or SSRIs late in third trimester of pregnancy have developed complications requiring prolonged hospitalization, respiratory support, & tube feeding

            Clinical worsening and suicide ideation may occur despite medication

            Postmarketing cases of QT interval prolongation and ventricular arrhythmia including torsade de pointes have been reported in patients treated with fluoxetine

            Neuroleptic malignant syndrome (NMS) reported in association with administration of antipsychotic drugs (eg, olanzapine); clinical manifestations of NMS are hyperpyrexia, muscle rigidity, altered mental status, and evidence of autonomic instability (irregular pulse or blood pressure, tachycardia, diaphoresis, and cardiac dysrhythmia)

            Drug reaction with eosinophilia and systemic symptoms (DRESS) reported with olanzapine exposure; DRESS may present with a cutaneous reaction (eg, rash or exfoliative dermatitis), eosinophilia, fever, and/or lymphadenopathy with systemic complications such as hepatitis, nephritis, pneumonitis, myocarditis, and/or pericarditis; discontinue treatment if DRESS is suspected

            Not approved in treatment of dementia-related psychosis; may increase incidence of CVA, TIA

            FDA Warning regarding off-label use for dementia in elderly

            Prolactin levels: Changes from normal to high prolactin levels observed in 3 controlled studies; incidence ranging from 28-47%

            May cause decreased libido, anorgasmia, erectile dysfunction, and abnormal ejaculation; priapism reported with SSRIs

            May cause somnolence, postural hypotension, motor and sensory instability, which may lead to falls and, consequently, fractures or other injuries; for patients with diseases, conditions, or medications that could exacerbate these effects, complete fall risk assessments when initiating antipsychotic treatment and recurrently for patients on long- term antipsychotic therapy

            Risk of developing tardive dyskinesia and likelihood that it will become irreversible are believed to increase as treatment duration and the total cumulative dose of antipsychotic drugs administered to the patient increase

            Seizures occurred in 0.2% fluoxetine/olanzapine-treated patients during open-label clinical studies

            In clinical trial and/or postmarketing experience, events of leukopenia/neutropenia have been reported temporally related to antipsychotic agents

            Esophageal dysmotility and aspiration associated with antipsychotic drug use; aspiration pneumonia is a common cause of morbidity and mortality in patients with advanced Alzheimer’s disease

            Risk of serotonin syndrome when used with other strong serotonergic drugs (including triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, buspirone, amphetamines, and St. John's Wort)

            Disruption of body’s ability to reduce core body temperature has been attributed to antipsychotic drugs

            Owing to the long elimination half-lives of fluoxetine and its major active metabolite, dosage changes will not fully be reflected in plasma for several weeks, affecting both strategies for titration to final dose and withdrawal from treatment

            Hyperglycemia/diabetes

            • Increased risk of hyperglycemia and diabetes; in some cases, hyperglycemia concomitant with use of atypical antipsychotics (of which olanzapine is a member) has been associated with ketoacidosis, hyperosmolar coma, or death
            • Monitor blood glucose of high-risk patients

            Sexual dysfunction

            • Use may cause symptoms of sexual dysfunction in both male and female patients; inform patients that they should discuss any changes in sexual function and potential management strategies with their healthcare provider
            • Use of SSRIs, may cause symptoms of sexual dysfunction; in male patients, SSRI use may result in ejaculatory delay or failure, decreased libido, and erectile dysfunction
            • In female patients, SSRI/SNRI use may result in decreased libido and delayed or absent orgasm
            • Important for prescribers to inquire about sexual function prior to initiation of therapy and to inquire specifically about changes in sexual function during treatment, because sexual function may not be spontaneously reported
            • When evaluating changes in sexual function, obtaining a detailed history (including timing of symptom onset) is important because sexual symptoms may have other causes, including underlying psychiatric disorder
            • Discuss potential management strategies to support patients in making informed decisions about treatment
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            Pregnancy & Lactation

            Pregnancy

            There is pregnancy exposure registry that monitors pregnancy outcomes in women exposed to psychiatric medications, during pregnancy; healthcare providers are encouraged to register patients by contacting the National Pregnancy Registry for Psychiatric Medications at 1-866-961-2388 or https://womensmentalhealth.org/clinical-and-research-programs/pregnancyregistry/

            Neonates exposed to antipsychotic drugs during the 3rd trimester of pregnancy are at risk for extrapyramidal and/or withdrawal symptoms following delivery

            These complications vary in severity; in some cases, symptoms have been self-limited, while in other cases neonates have required intensive care unit support and prolonged hospitalization

            Treatment of Pregnant Women during the First Trimester with Fluoxetine: There are no adequate and well-controlled clinical studies on the use of fluoxetine in pregnant women, but 1 prospective cohort study conducted by the European Network of Teratology Information Services reported an increased risk of cardiovascular malformations in infants born to women (N = 253) exposed to fluoxetine during the first trimester of pregnancy compared to infants of women (N = 1,359) who were not exposed to fluoxetine

            SSRI use late in the third trimester associated with complications in newborns and may require prolonged hospitalization, respiratory support, and tube feeding

            Women who discontinue antidepressants during pregnancy are more likely to experience a relapse of major depression than women who continue antidepressants; consider risk of untreated depression when discontinuing or changing treatment with antidepressant medication during pregnancy and postpartum

            Antipsychotic drug exposure

            • Extrapyramidal and/or withdrawal symptoms, including agitation, hypertonia, hypotonia, tremor, somnolence, respiratory distress and feeding disorder reported in neonates who were exposed to antipsychotic drugs, including olanzapine, during third trimester of pregnancy; these symptoms have varied in severity
            • Monitor neonates for extrapyramidal and/or withdrawal symptoms and manage symptoms appropriately; some neonates recovered within hours or days without specific treatment; others required prolonged hospitalization

            Fluoxetine drug exposure

            • Neonates exposed to fluoxetine and other SSRIs or SNRIs late in third trimester have developed complications requiring prolonged hospitalization, respiratory support, and tube feeding; such complications can arise immediately upon delivery; reported clinical findings have included respiratory distress, cyanosis, apnea, seizures, temperature instability, feeding difficulty, vomiting, hypoglycemia, hypotonia, hypertonia, hyperreflexia, tremor, jitteriness, irritability, and constant crying
            • These findings are consistent with either a direct toxic effect of SSRIs and SNRIs or possibly a drug discontinuation syndrome; it should be noted that, in some cases, the clinical picture is consistent with serotonin syndrome

            Females and males of reproductive potential

            • Females: Based on pharmacologic action of olanzapine (dopamine D2 receptor blockade), treatment with drug combination may result in an increase in serum prolactin levels, which may lead to a reversible reduction in fertility in females of reproductive potential

            Persistent pulmonary hypertension of the newborn

            • Potential risk of persistent pulmonary hypertension of the newborn (PPHN) when used during pregnancy
            • Initial Public Health Advisory in 2006 was based on a single published study; since then, there have been conflicting findings from new studies, making it unclear whether use of SSRIs during pregnancy can cause PPHN
            • FDA has reviewed the additional new study results and has concluded that, given the conflicting results from different studies, it is premature to reach any conclusion about a possible link between SSRI use in pregnancy and PPHN
            • FDA recommendation: FDA advises health care professionals not to alter their current clinical practice of treating depression during pregnancy and to report any adverse events to the FDA MedWatch program

            Animal data

            • In animal studies, administration of combination of olanzapine and fluoxetine during period of organogenesis resulted in adverse effects on development (decreased fetal body weights in rats and rabbits and retarded skeletal ossification in rabbits) at maternally toxic doses greater than those used clinically
            • When administered to rats throughout pregnancy and lactation, an increase in early postnatal mortality was observed at doses similar to those used clinically

            Lactation

            Consider developmental and health benefits of breastfeeding along with mother’s clinical need for therapy and any potential adverse effects on breastfed child from therapy or underlying maternal condition

            Infants exposed to drug combination should be monitored for agitation, irritability, poor feeding, poor weight gain, excess sedation, and extrapyramidal symptoms (tremors and abnormal muscle movements)

            Olanzapine

            • In a study in lactating, healthy women, olanzapine was excreted in breast milk
            • Mean infant dose at steady state was estimated to be 1.8% of the maternal olanzapine dose
            • It is recommended that women receiving olanzapine should not breastfeed

            Fluoxetine

            • Excreted in human breast milk
            • In 1 breast milk sample, the concentration of fluoxetine plus norfluoxetine was 70.4 ng/mL; concentration in the mother’s plasma was 295 ng/mL

            Pregnancy Categories

            A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

            B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

            C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

            D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

            X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

            NA: Information not available.

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            Pharmacology

            Mechanism of Action

            Fluoxetine: Inhibits CNS neuron setotonin reuptake with minimal or no effect on norepinephrine or dopamine reuptake; does not bind to alpha-adrenergic, histamine, or cholinergic receptors

            Olanzapine: Potent antagonist of dopamine 1-3, histamine H1, serotonin 5-HT2A and 5-HT2C, and alpha1-adrenergic receptors; shows moterate antagonism for 5-HT3, and muscarinic M1-5 receptors; binds to GABA-A, benzodiazepine, and beta-adrenergic receptors

            Absorption

            Peak plasma time: 4-6 hr (50 mg/12 mg-dose); 6 hr (olanzapine); 6-8 hr (fluoxetine)

            Peak plasma concentration: 15-55 ng/mL (fluoxetine)

            Distribution

            Vd: ~1,000 L (olanzapine)

            Protein binding: 93% (olanzapine); ~94.5% (fluoxetine)

            Mechanism

            Direct glucuronidation and CYP450-mediated oxidation are the primary metabolic pathways for olanzapine

            CYP2D6-mediated oxidation appears to be a minor metabolic pathway in vivo, because clearance of olanzapine is not reduced in subjects who are deficient in this enzyme

            Fluoxetine is extensively metabolized in the liver to its active metabolite, norfluoxetine, via CYP2D6 pathway

            Excretion

            Half-life: 21-54 hr (olanzapine)

            Clearance: 12-47 L/hr (olanzapine)

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            Administration

            Oral Administration

            Administer orally once daily in the evening

            If missed dose, take the missed dose as soon possible; if it is almost time for the next dose, skip the missed dose and take next dose at the regular time; do not take two doses at once

            Storage

            Tablets: Store at 25°C (77°F); excursions permitted to 15-30°C (59-86°F); keep tightly closed and protect from moisture

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            Images

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            Patient Handout

            A Patient Handout is not currently available for this monograph.
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            Formulary

            FormularyPatient Discounts

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            Tier Description
            1 This drug is available at the lowest co-pay. Most commonly, these are generic drugs.
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            Code Definition
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            Medscape prescription drug monographs are based on FDA-approved labeling information, unless otherwise noted, combined with additional data derived from primary medical literature.