isoflurane (Rx)

Brand and Other Names:Forane
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Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

inhalation solution

  • 100mL
  • 250mL

Anesthesia Induction & Maintenance

Use calibrated vaporizer

Induction: 1.5-3% can produce surgical anesthesia in 7-10 minutes

Maintenance: 1-2.5% with nitrous oxide

Additional 0.5-1% may be needed if given with oxygen alone

Safety & efficacy not established

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Interactions

Interaction Checker

and isoflurane

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            Contraindicated (2)

            • dronedarone

              isoflurane and dronedarone both increase QTc interval. Contraindicated.

            • thioridazine

              isoflurane and thioridazine both increase QTc interval. Contraindicated.

            Serious - Use Alternative (166)

            • alfuzosin

              alfuzosin and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • amiodarone

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

            • amisulpride

              amisulpride and isoflurane both increase QTc interval. Avoid or Use Alternate Drug. ECG monitoring is recommended if coadministered.

            • anagrelide

              isoflurane and anagrelide both increase QTc interval. Avoid or Use Alternate Drug.

            • apomorphine

              isoflurane and apomorphine both increase QTc interval. Avoid or Use Alternate Drug.

            • aripiprazole

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

            • arsenic trioxide

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

            • artemether

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

            • artemether/lumefantrine

              artemether/lumefantrine and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • asenapine

              isoflurane and asenapine both increase QTc interval. Avoid or Use Alternate Drug.

            • asenapine transdermal

              asenapine transdermal and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • atomoxetine

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

            • azithromycin

              isoflurane and azithromycin both increase QTc interval. Avoid or Use Alternate Drug.

            • bedaquiline

              bedaquiline and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • benzhydrocodone/acetaminophen

              benzhydrocodone/acetaminophen, isoflurane. 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. Increased risk of hypotension if ability to maintain blood pressure has been compromised by a reduced blood volume or concurrent administration of certain CNS depressant drugs (eg, phenothiazines or general anesthetics).

            • buprenorphine

              isoflurane and buprenorphine both increase QTc interval. Avoid or Use Alternate Drug.

            • ceritinib

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

            • chloroquine

              chloroquine and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • chlorpromazine

              isoflurane and chlorpromazine both increase QTc interval. Avoid or Use Alternate Drug.

            • ciprofloxacin

              isoflurane and ciprofloxacin both increase QTc interval. Avoid or Use Alternate Drug.

            • citalopram

              citalopram and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • clarithromycin

              clarithromycin and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • clozapine

              clozapine and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • crizotinib

              crizotinib and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • dasatinib

              dasatinib and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • degarelix

              degarelix and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • deutetrabenazine

              deutetrabenazine and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • dexfenfluramine

              isoflurane increases toxicity of dexfenfluramine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • dexmethylphenidate

              isoflurane increases toxicity of dexmethylphenidate by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • dextroamphetamine

              isoflurane increases toxicity of dextroamphetamine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • diethylpropion

              isoflurane increases toxicity of diethylpropion by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • disopyramide

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

            • dobutamine

              isoflurane increases toxicity of dobutamine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • dofetilide

              isoflurane and dofetilide both increase QTc interval. Avoid or Use Alternate Drug.

            • dolasetron

              dolasetron and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • donepezil

              donepezil and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • dopamine

              isoflurane increases toxicity of dopamine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • droperidol

              isoflurane and droperidol both increase QTc interval. Avoid or Use Alternate Drug.

            • efavirenz

              efavirenz and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • eliglustat

              isoflurane and eliglustat both increase QTc interval. Avoid or Use Alternate Drug.

            • encorafenib

              encorafenib and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • entrectinib

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

            • ephedrine

              isoflurane increases toxicity of ephedrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • epinephrine

              isoflurane increases toxicity of epinephrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • eribulin

              eribulin and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • erythromycin base

              isoflurane and erythromycin base both increase QTc interval. Avoid or Use Alternate Drug.

            • erythromycin ethylsuccinate

              isoflurane and erythromycin ethylsuccinate both increase QTc interval. Avoid or Use Alternate Drug.

            • erythromycin lactobionate

              isoflurane and erythromycin lactobionate both increase QTc interval. Avoid or Use Alternate Drug.

            • erythromycin stearate

              isoflurane and erythromycin stearate both increase QTc interval. Avoid or Use Alternate Drug.

            • escitalopram

              isoflurane and escitalopram both increase QTc interval. Avoid or Use Alternate Drug.

            • fenfluramine

              isoflurane increases toxicity of fenfluramine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • fentanyl

              fentanyl, isoflurane. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

            • fentanyl intranasal

              fentanyl intranasal, isoflurane. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

            • fentanyl transdermal

              fentanyl transdermal, isoflurane. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

            • fentanyl transmucosal

              fentanyl transmucosal, isoflurane. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Coadministration with other CNS depressants, such as skeletal muscle relaxants, may cause respiratory depression, hypotension, profound sedation, coma, and/or death. Consider dose reduction of either or both agents to avoid serious adverse effects. Monitor for hypotension, respiratory depression, and profound sedation.

            • fexinidazole

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

            • fingolimod

              fingolimod and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • flecainide

              isoflurane and flecainide both increase QTc interval. Avoid or Use Alternate Drug.

            • fluconazole

              isoflurane and fluconazole both increase QTc interval. Avoid or Use Alternate Drug.

            • fluoxetine

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

            • fluvoxamine

              isoflurane and fluvoxamine both increase QTc interval. Avoid or Use Alternate Drug.

            • foscarnet

              isoflurane and foscarnet both increase QTc interval. Avoid or Use Alternate Drug.

            • gemifloxacin

              gemifloxacin and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • gemtuzumab

              isoflurane and gemtuzumab both increase QTc interval. Avoid or Use Alternate Drug.

            • gilteritinib

              gilteritinib and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • glasdegib

              isoflurane and glasdegib both increase QTc interval. Avoid or Use Alternate Drug.

            • goserelin

              isoflurane and goserelin both increase QTc interval. Avoid or Use Alternate Drug.

            • granisetron

              granisetron and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • haloperidol

              isoflurane and haloperidol both increase QTc interval. Avoid or Use Alternate Drug.

            • histrelin

              isoflurane and histrelin both increase QTc interval. Avoid or Use Alternate Drug.

            • hydrocodone

              hydrocodone, isoflurane. 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. Increased risk of hypotension if ability to maintain blood pressure has been compromised by a reduced blood volume or concurrent administration of certain CNS depressant drugs (eg, phenothiazines or general anesthetics).

            • hydroxychloroquine sulfate

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

            • hydroxyzine

              hydroxyzine and isoflurane both increase QTc interval. Avoid or Use Alternate Drug.

            • ibutilide

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

            • iloperidone

              isoflurane and iloperidone both increase QTc interval. Avoid or Use Alternate Drug.

            • inotuzumab

              isoflurane and inotuzumab both increase QTc interval. Avoid or Use Alternate Drug.

            • isoproterenol

              isoflurane increases toxicity of isoproterenol by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • itraconazole

              isoflurane and itraconazole both increase QTc interval. Avoid or Use Alternate Drug.

            • ivosidenib

              isoflurane and ivosidenib both decrease QTc interval. Avoid or Use Alternate Drug.

            • lapatinib

              isoflurane and lapatinib both increase QTc interval. Avoid or Use Alternate Drug.

            • lefamulin

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

            • lenvatinib

              isoflurane and lenvatinib both increase QTc interval. Avoid or Use Alternate Drug.

            • leuprolide

              isoflurane and leuprolide both increase QTc interval. Avoid or Use Alternate Drug.

            • levofloxacin

              isoflurane and levofloxacin both increase QTc interval. Avoid or Use Alternate Drug.

            • lisdexamfetamine

              isoflurane increases toxicity of lisdexamfetamine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • lithium

              isoflurane and lithium both increase QTc interval. Avoid or Use Alternate Drug.

            • lofexidine

              isoflurane and lofexidine both increase QTc interval. Avoid or Use Alternate Drug.

            • loperamide

              isoflurane and loperamide both increase QTc interval. Avoid or Use Alternate Drug.

            • lopinavir

              isoflurane and lopinavir both increase QTc interval. Avoid or Use Alternate Drug.

            • macimorelin

              isoflurane and macimorelin both increase QTc interval. Avoid or Use Alternate Drug.

            • maprotiline

              isoflurane and maprotiline both increase QTc interval. Avoid or Use Alternate Drug.

            • mefloquine

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

            • methadone

              isoflurane and methadone both increase QTc interval. Avoid or Use Alternate Drug.

            • methamphetamine

              isoflurane increases toxicity of methamphetamine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • methylphenidate

              isoflurane increases toxicity of methylphenidate by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of acute hypertensive episode.

            • metoclopramide intranasal

              isoflurane, 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.

            • midodrine

              isoflurane increases toxicity of midodrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • midostaurin

              isoflurane and midostaurin both increase QTc interval. Avoid or Use Alternate Drug.

            • mifepristone

              isoflurane and mifepristone both increase QTc interval. Avoid or Use Alternate Drug.

            • mirtazapine

              isoflurane and mirtazapine both increase QTc interval. Avoid or Use Alternate Drug.

            • mobocertinib

              isoflurane and mobocertinib both increase QTc interval. Avoid or Use Alternate Drug.

            • moxifloxacin

              isoflurane and moxifloxacin both increase QTc interval. Avoid or Use Alternate Drug.

            • nilotinib

              isoflurane and nilotinib both increase QTc interval. Avoid or Use Alternate Drug.

            • norepinephrine

              isoflurane increases toxicity of norepinephrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • octreotide

              isoflurane and octreotide both increase QTc interval. Avoid or Use Alternate Drug.

            • ofloxacin

              isoflurane and ofloxacin both increase QTc interval. Avoid or Use Alternate Drug.

            • olanzapine

              isoflurane 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

            • ondansetron

              isoflurane and ondansetron both increase QTc interval. Avoid or Use Alternate Drug.

            • osimertinib

              isoflurane and osimertinib both increase QTc interval. Avoid or Use Alternate Drug.

            • oxaliplatin

              isoflurane and oxaliplatin both increase QTc interval. Avoid or Use Alternate Drug.

            • oxytocin

              isoflurane and oxytocin both increase QTc interval. Avoid or Use Alternate Drug.

            • ozanimod

              isoflurane and ozanimod both increase QTc interval. Avoid or Use Alternate Drug.

            • paliperidone

              isoflurane and paliperidone both increase QTc interval. Avoid or Use Alternate Drug.

            • panobinostat

              isoflurane and panobinostat both increase QTc interval. Avoid or Use Alternate Drug.

            • pasireotide

              isoflurane and pasireotide both increase QTc interval. Avoid or Use Alternate Drug.

            • pazopanib

              isoflurane and pazopanib both increase QTc interval. Avoid or Use Alternate Drug.

            • pentamidine

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

            • phendimetrazine

              isoflurane increases toxicity of phendimetrazine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • phentermine

              isoflurane increases toxicity of phentermine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • phenylephrine

              isoflurane increases toxicity of phenylephrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • phenylephrine PO

              isoflurane increases toxicity of phenylephrine PO by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • pimavanserin

              isoflurane and pimavanserin both increase QTc interval. Avoid or Use Alternate Drug.

            • pimozide

              isoflurane and pimozide both increase QTc interval. Contraindicated.

            • pitolisant

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

            • ponesimod

              isoflurane and ponesimod both increase QTc interval. Avoid or Use Alternate Drug.

            • posaconazole

              isoflurane and posaconazole both increase QTc interval. Avoid or Use Alternate Drug.

            • primaquine

              isoflurane and primaquine both increase QTc interval. Avoid or Use Alternate Drug.

            • procainamide

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

            • propafenone

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

            • propylhexedrine

              isoflurane increases toxicity of propylhexedrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • pseudoephedrine

              isoflurane increases toxicity of pseudoephedrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • quetiapine

              isoflurane and quetiapine both increase QTc interval. Avoid or Use Alternate Drug.

            • quinine

              isoflurane and quinine both increase QTc interval. Avoid or Use Alternate Drug.

            • ranolazine

              isoflurane and ranolazine both increase QTc interval. Avoid or Use Alternate Drug.

            • ribociclib

              isoflurane and ribociclib both increase QTc interval. Avoid or Use Alternate Drug.

            • rilpivirine

              isoflurane and rilpivirine both increase QTc interval. Avoid or Use Alternate Drug.

            • risperidone

              isoflurane and risperidone both increase QTc interval. Avoid or Use Alternate Drug.

            • romidepsin

              isoflurane and romidepsin both increase QTc interval. Avoid or Use Alternate Drug.

            • ropeginterferon alfa 2b

              ropeginterferon alfa 2b and isoflurane both increase Other (see comment). Avoid or Use Alternate Drug. Narcotics, hypnotics or sedatives can produce additive neuropsychiatric side effects. Avoid use and monitor patients receiving the combination for effects of excessive CNS toxicity.

            • saquinavir

              isoflurane and saquinavir both increase QTc interval. Avoid or Use Alternate Drug.

            • selpercatinib

              isoflurane and selpercatinib both increase QTc interval. Avoid or Use Alternate Drug.

            • serdexmethylphenidate/dexmethylphenidate

              isoflurane increases toxicity of serdexmethylphenidate/dexmethylphenidate by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • sertraline

              isoflurane and sertraline both increase QTc interval. Avoid or Use Alternate Drug.

            • siponimod

              isoflurane and siponimod both increase QTc interval. Avoid or Use Alternate Drug.

            • solifenacin

              isoflurane and solifenacin both increase QTc interval. Avoid or Use Alternate Drug.

            • sorafenib

              isoflurane and sorafenib both increase QTc interval. Avoid or Use Alternate Drug.

            • sotalol

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

            • sufentanil SL

              sufentanil SL, isoflurane. 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.

            • sunitinib

              isoflurane and sunitinib both increase QTc interval. Avoid or Use Alternate Drug.

            • tacrolimus

              isoflurane and tacrolimus both increase QTc interval. Avoid or Use Alternate Drug.

            • telavancin

              isoflurane and telavancin both increase QTc interval. Avoid or Use Alternate Drug.

            • tetrabenazine

              isoflurane and tetrabenazine both increase QTc interval. Avoid or Use Alternate Drug.

            • toremifene

              isoflurane and toremifene both increase QTc interval. Avoid or Use Alternate Drug.

            • trazodone

              isoflurane and trazodone both increase QTc interval. Avoid or Use Alternate Drug.

            • triclabendazole

              isoflurane and triclabendazole both increase QTc interval. Avoid or Use Alternate Drug.

            • triptorelin

              isoflurane and triptorelin both increase QTc interval. Avoid or Use Alternate Drug.

            • vandetanib

              isoflurane and vandetanib both increase QTc interval. Avoid or Use Alternate Drug.

            • vardenafil

              isoflurane and vardenafil both increase QTc interval. Avoid or Use Alternate Drug.

            • vemurafenib

              isoflurane and vemurafenib both increase QTc interval. Avoid or Use Alternate Drug.

            • venlafaxine

              isoflurane and venlafaxine both decrease QTc interval. Avoid or Use Alternate Drug.

            • voclosporin

              isoflurane and voclosporin both increase QTc interval. Avoid or Use Alternate Drug.

            • voriconazole

              isoflurane and voriconazole both increase QTc interval. Avoid or Use Alternate Drug.

            • vorinostat

              isoflurane and vorinostat both increase QTc interval. Avoid or Use Alternate Drug.

            • xylometazoline

              isoflurane increases toxicity of xylometazoline by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • yohimbine

              isoflurane increases toxicity of yohimbine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.

            • ziprasidone

              isoflurane and ziprasidone both increase QTc interval. Avoid or Use Alternate Drug.

            Monitor Closely (31)

            • albuterol

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

            • amitriptyline

              isoflurane and amitriptyline both increase QTc interval. Use Caution/Monitor.

            • arformoterol

              arformoterol and isoflurane both increase QTc interval. Use Caution/Monitor.

            • benazepril

              isoflurane, benazepril. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increases risk of hypotension.

            • brexanolone

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

            • buprenorphine, long-acting injection

              isoflurane 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.

            • captopril

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

            • clomipramine

              isoflurane and clomipramine both increase QTc interval. Use Caution/Monitor.

            • daridorexant

              isoflurane and daridorexant both increase sedation. Modify Therapy/Monitor Closely. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment.

            • desipramine

              isoflurane and desipramine both increase QTc interval. Use Caution/Monitor.

            • difelikefalin

              difelikefalin and isoflurane both increase sedation. Use Caution/Monitor.

            • doxepin

              doxepin and isoflurane both increase QTc interval. Use Caution/Monitor.

            • esketamine intranasal

              esketamine intranasal, isoflurane. Either increases toxicity of the other by sedation. Use Caution/Monitor.

            • fluphenazine

              isoflurane and fluphenazine both increase QTc interval. Use Caution/Monitor.

            • fostemsavir

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

            • ganaxolone

              isoflurane and ganaxolone both increase sedation. Use Caution/Monitor.

            • imipramine

              isoflurane and imipramine both increase QTc interval. Use Caution/Monitor.

            • lasmiditan

              lasmiditan, isoflurane. 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, isoflurane. 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.

            • midazolam intranasal

              midazolam intranasal, isoflurane. 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.

            • nortriptyline

              isoflurane and nortriptyline both increase QTc interval. Use Caution/Monitor.

            • oliceridine

              oliceridine, isoflurane. 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. Increased risk of hypotension if ability to maintain blood pressure has been compromised by a reduced blood volume or concurrent administration of certain CNS depressant drugs (eg, phenothiazines or general anesthetics).

            • osilodrostat

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

            • perphenazine

              isoflurane and perphenazine both increase QTc interval. Use Caution/Monitor.

            • prochlorperazine

              isoflurane and prochlorperazine both decrease QTc interval. Use Caution/Monitor.

            • promethazine

              isoflurane and promethazine both decrease QTc interval. Use Caution/Monitor.

            • protriptyline

              isoflurane and protriptyline both increase QTc interval. Use Caution/Monitor.

            • quinidine

              isoflurane and quinidine both increase QTc interval. Use Caution/Monitor.

            • stiripentol

              stiripentol, isoflurane. 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.

            • trifluoperazine

              isoflurane and trifluoperazine both decrease QTc interval. Use Caution/Monitor.

            • trimipramine

              isoflurane and trimipramine both increase QTc interval. Use Caution/Monitor.

            Minor (0)

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              Adverse Effects

              1-10%

              Nausea

              Vomiting

              Shivering

              <1%

              Dose-dependent hypotension

              Arrhythmias

              Malignant hyperthermia (rare)

              Elevations in white blood count

              May decrease creatinine and increase BUN

              Ileus, severe (fatal)

              Hepatic dysfunction (postoperative period) (rare)

              Respiratory depression may occur (rare)

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              Warnings

              Contraindications

              Hypersensitivity to isoflurane & halogenated agents

              Genetic susceptibility to malignant hyperthermia

              Patients in whom general anesthesia contraindicated

              History of confirmed hepatitis due to a halogenated inhalational anesthetic or a history of unexplained moderate to severe hepatic dysfunction (eg, jaundice associated with fever and/or eosinophilia) after anesthesia with isoflurane or other halogenated inhalational anesthetics

              Cautions

              Caution in coronary heart disease

              May decrease renal and hepatic blood flow

              Postoperative hepatic dysfunction and hepatitis reported

              Adequate data have not been developed to establish its application in obstetrical anesthesia

              Should not be used as a sole agent of induction in patients with ventricular dysfunction

              Therapy should only be administered in an adequately equipped anesthetizing environment by those who are familiar with the pharmacology of the drug and qualified by training and experience to manage the anesthetized patient

              All patients receiving the drug should be continually monitored (eg, monitoring of the electrocardiogram, blood pressure, oxygen saturation, and end tidal CO2)

              The drug is a profound respiratory depressant; excessive respiratory depression may be related to depth of anesthesia and respond to decreasing the inspired concentration of isoflurane

              The depressant effect is accentuated by concurrent use of opioids and other respiratory depressants; respiration should be closely monitored and assisted or controlled ventilation employed when necessary

              With the exception of neonates, isoflurane MAC decreases with increasing age

              QTc prolongation, with rare instances of torsade de pointes, reported; monitor QT interval when administering the drug to susceptible patients

              Regardless of the anesthetics employed, maintenance of normal hemodynamics is important to the avoidance of myocardial ischemia in patients with coronary artery disease

              Isoflurane can cause dose-dependent coronary vasodilation and has been shown to divert blood from collateral-dependent myocardium to normally perfused areas in an animal model (“coronary steal”); monitor for signs of inadequate myocardial perfusion via hemodynamic monitors (eg, ECG, blood pressure) during administration; consider additional cardiac monitoring in patients with known coronary artery disease, as clinically necessary

              Isoflurane causes a dose-dependent reduction in systemic vascular resistance and blood pressure; particular care must be taken when selecting the dosage for patients who are hypovolemic, hypotensive, or otherwise hemodynamically compromised, eg, due to concomitant medications

              Increased blood loss comparable to that seen with halothane observed in patients undergoing abortions

              Allergic-type hypersensitivity reactions, including anaphylaxis, reported with therapy; manifestations of such reactions have included hypotension, rash, difficulty breathing and cardiovascular collapse

              The drug markedly increases cerebral blood flow at deeper levels of anesthesia to produce a transient increase in intracranial pressure; in patients with or at risk for elevations of intracranial pressure (ICP), administer isoflurane in conjunction with ICP- reducing strategies, as clinically appropriate

              The color indicator of most CO2 absorbents does not necessarily change as a result of desiccation; therefore, the lack of significant color change should not be taken as assurance of adequate hydration of the CO2 absorbent material; CO2 absorbents should be replaced routinely regardless of the state of color indicator following current manufacturer’s guidelines for use of anesthesiology equipment

              Reactions reported following occupational exposure to the drug include dyspnea, bronchospasm, stridor, cough, dizziness, paresthesia, hepatic reactions, flushing rash, contact dermatitis, erythema, periorbital edema, eye irritation, conjunctival hyperemia, and headache

              Hepatic reactions

              • Cases of mild, moderate and severe postoperative hepatic dysfunction or hepatitis with or without jaundice, including fatal hepatic necrosis and hepatic failure, reported
              • Such reactions can represent hypersensitivity hepatitis, a known risk of exposure to halogenated anesthetics, including isoflurane
              • As with other halogenated anesthetic agents, the drug may cause sensitivity hepatitis in patients sensitized by previous exposure to halogenated anesthetics
              • Clinical judgment should be exercised when isoflurane the drug is used in patients with underlying hepatic conditions or under treatment with drugs known to cause hepatic dysfunction
              • As with all halogenated anesthetics, repeated anesthetics within a short period of time may result in increased effects, particularly in patients with underlying hepatic conditions, or additive effects in patients treated with drugs known to cause hepatic dysfunction
              • Evaluate the need for repeated exposure in each individual patient and adjust the dose of isoflurane based on signs and symptoms of adequate depth of anesthesia if repeated exposure in a short period of time is clinically indicated

              Malignant hyperthermia

              • In susceptible individuals, isoflurane anesthesia may trigger a skeletal muscle hypermetabolic state leading to high oxygen demand and the clinical syndrome known as malignant hyperthermia
              • The syndrome includes nonspecific features such as muscle rigidity, tachycardia, tachypnea, cyanosis, arrhythmias, and unstable blood pressure; it should also be noted that many of these nonspecific signs may appear with light anesthesia, acute hypoxia, etc
              • An increase in overall metabolism may be reflected in an elevated temperature, (which may rise rapidly early or late in the case, but usually is not the first sign of augmented metabolism) and an increased usage of the CO2 absorption system (hot canister)
              • PaO2 and pH may decrease, and hyperkalemia and a base deficit may appear; treatment includes discontinuance of triggering agents (eg, isoflurane), administration of intravenous dantrolene sodium, and application of supportive therapy
              • Such therapy includes vigorous efforts to restore body temperature to normal, respiratory and circulatory support as indicated, and management of electrolyte- fluid-acid-base derangements
              • Consult prescribing information for dantrolene sodium intravenous for additional information on patient management
              • Renal failure may appear later, and urine flow should be sustained if possible; fatal outcome of malignant hyperthermia has been reported with isoflurane

              Pediatric use

              • During the induction of anesthesia, saliva flow and tracheobronchial secretion can increase and can be the cause of larynogospasm, particularly in children

              Perioperative Hyperkalemia

              • Inhaled anesthetics associated with rare increases in serum potassium levels that have resulted in cardiac arrhythmias and death in pediatric patients postoperatively
              • Patients with latent as well as overt neuromuscular disease, particularly Duchenne muscular dystrophy, appear to be most vulnerable
              • Concomitant use of succinylcholine has been associated with most, but not all, of these cases
              • Elevated serum creatinine kinase levels and, in some cases, changes in urine consistent with myoglobinuria observed
              • Despite similar presentation to malignant hyperthermia, none of affected patients exhibited signs or symptoms of muscle rigidity or hypermetabolic state
              • Early and aggressive intervention to treat hyperkalemia and resistant arrhythmias recommended
              • Evaluation for latent neuromuscular disease recomended

              General anesthetics and sedation drugs in young children and pregnant women

              • Brain development
                • Prolonged or repeated exposure may result in negative effects on fetal or young children’s brain development
                • Caution with use during surgeries or procedures in children younger than 3 yr or in pregnant women during their third trimester
                • Assess the risk:benefit ratio in these populations, especially for prolonged procedures (ie, >3 hr) or multiple procedures
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              Pregnancy & Lactation

              Pregnancy

              There are no adequate and well-controlled studies in pregnant women; in animal reproduction studies, embryofetal toxicity was noted in pregnant mice exposed to 0.075% (increased post implantation losses) and 0.3% isoflurane (increased post implantation losses and decreased live- birth index) during organogenesis

              Lactation

              Due to insufficient information regarding the excretion of isoflurane in human milk, the potential risks and benefits for each specific patient should be carefully considered before isoflurane is administered to nursing women

              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

              Volatile liquid inhalation anesthetic

              Pharmacokinetics

              Onset: Rapid (7-10 min)

              Duration: Short (depends on blood concentration)

              Minimum Alveolar Conc: 1.3%

              Metabolism: Liver (0.2%)

              Pharmacogenomics

              Increased incidence of malignant hyperthermia with use of volatile anesthetics or depolarizing neuromuscular blockers in patients with gene mutations in ryanodine receptor (RYR1) or calcium channel alpha (1S)- subunit gene (CACNA1S)

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              Images

              BRAND FORM. UNIT PRICE PILL IMAGE
              isoflurane inhalation
              -
              99.9 % liquid
              isoflurane inhalation
              -
              99.9 % liquid

              Copyright © 2010 First DataBank, Inc.

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              Patient Handout

              Patient Education
              isoflurane inhalation

              NO MONOGRAPH AVAILABLE AT THIS TIME

              USES: Consult your pharmacist.

              HOW TO USE: Consult your pharmacist.

              SIDE EFFECTS: Consult your pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

              PRECAUTIONS: Consult your pharmacist.

              DRUG INTERACTIONS: Consult your pharmacist.Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

              OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.

              NOTES: No monograph available at this time.

              MISSED DOSE: Consult your pharmacist.

              STORAGE: Consult your pharmacist.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

              Information last revised July 2016. Copyright(c) 2022 First Databank, Inc.

              IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

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              Formulary

              FormularyPatient Discounts

              Adding plans allows you to compare formulary status to other drugs in the same class.

              To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.

              Adding plans allows you to:

              • View the formulary and any restrictions for each plan.
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              • Compare formulary status to other drugs in the same class.
              • Access your plan list on any device – mobile or desktop.

              The above information is provided for general informational and educational purposes only. Individual plans may vary and formulary information changes. Contact the applicable plan provider for the most current information.

              Tier Description
              1 This drug is available at the lowest co-pay. Most commonly, these are generic drugs.
              2 This drug is available at a middle level co-pay. Most commonly, these are "preferred" (on formulary) brand drugs.
              3 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs.
              4 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
              5 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
              6 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
              NC NOT COVERED – Drugs that are not covered by the plan.
              Code Definition
              PA Prior Authorization
              Drugs that require prior authorization. This restriction requires that specific clinical criteria be met prior to the approval of the prescription.
              QL Quantity Limits
              Drugs that have quantity limits associated with each prescription. This restriction typically limits the quantity of the drug that will be covered.
              ST Step Therapy
              Drugs that have step therapy associated with each prescription. This restriction typically requires that certain criteria be met prior to approval for the prescription.
              OR Other Restrictions
              Drugs that have restrictions other than prior authorization, quantity limits, and step therapy associated with each prescription.
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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.