phentermine (Rx)

Brand and Other Names:Adipex P, Lomaira
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Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

capsule, HCl salt: Schedule IV

  • 15mg (generics)
  • 30mg (generics)
  • 37.5mg (Adipex P, generics)

tablet, HCl salt: Schedule IV

  • 8mg (Lomaira)
  • 37.5mg (Adipex P, generics)

Obesity

Short-term (few weeks) adjunctive use as part of weight-reduction regimen based on exercise, behavioral modification, and caloric restriction in management of exogenous obesity for patients with initial body mass index (BMI) ≥30 kg/m² or ≥27 kg/m² in presence of other risk factors (eg, controlled hypertension, diabetes, hyperlipidemia)

Adjust dosing according to patient's needs to achieve adequate response with lowest effective dosage

Adipex P or generic

  • 15-37.5 mg/day PO in single daily dose or divided q12hr before breakfast or 1-2 hr after breakfast

Lomaira

  • Typical dose is 8mg PO TID 30 minutes before meals

Dosage Forms & Strengths

capsule, HCl salt: Schedule IV

  • 15mg (generics)
  • 30mg (generics)
  • 37.5mg (Adipex P, generics)

tablet, HCl salt: Schedule IV

  • 8mg (Lomaira)
  • 37.5mg (Adipex P, generics)

Obesity

Short-term (few weeks) adjunctive use as part of weight-reduction regimen based on exercise, behavioral modification, and caloric restriction in management of exogenous obesity for patients with initial BMI ≥30 kg/m² or ≥27 kg/m² in presence of other risk factors (eg, controlled hypertension, diabetes, hyperlipidemia)

<16 years: Safety and efficacy not established

≥16 years

  • Adjust dosing according to patient's needs to achieve adequate response with lowest effective dosage
  • Adipex P or generic
    • 15-37.5 mg/day PO in single daily dose or divided q12hr before breakfast or 1-2 hr after breakfast
  • Lomaira
    • Typical dose is 8mg PO TID 30 minutes before meals
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Interactions

Interaction Checker

and phentermine

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            Contraindicated (8)

            • iobenguane I 123

              phentermine decreases effects of iobenguane I 123 by receptor binding competition. Contraindicated. If clinically appropriate, discontinue drugs that compete for NE receptor sites for at least 5 half-lives; may cause false-negative imaging results.

            • isocarboxazid

              isocarboxazid increases effects of phentermine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            • linezolid

              linezolid increases effects of phentermine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            • methylphenidate

              phentermine increases effects of methylphenidate by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            • phenelzine

              phenelzine increases effects of phentermine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            • procarbazine

              procarbazine increases effects of phentermine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            • selegiline transdermal

              selegiline transdermal increases effects of phentermine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            • tranylcypromine

              tranylcypromine increases effects of phentermine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            Serious - Use Alternative (40)

            • amitriptyline

              amitriptyline, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

            • amoxapine

              amoxapine, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

            • cabergoline

              cabergoline, phentermine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.

            • citalopram

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

            • clomipramine

              clomipramine, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

            • desflurane

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

            • desipramine

              desipramine, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

            • dihydroergotamine

              dihydroergotamine, phentermine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.

            • dihydroergotamine intranasal

              dihydroergotamine intranasal, phentermine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.

            • doxapram

              doxapram increases effects of phentermine by pharmacodynamic synergism. Avoid or Use Alternate Drug. Additive pressor effect.

            • doxepin

              doxepin, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

            • duloxetine

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

            • ergoloid mesylates

              ergoloid mesylates, phentermine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.

            • ergotamine

              ergotamine, phentermine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.

            • escitalopram

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

            • ether

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

            • fluoxetine

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

            • fluvoxamine

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

            • imipramine

              imipramine, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

            • iobenguane I 131

              phentermine will decrease the level or effect of iobenguane I 131 by Other (see comment). Avoid or Use Alternate Drug. Based on the mechanism of action of iobenguane, drugs that reduce catecholamine uptake or that deplete catecholamine stores may interfere with iobenguane uptake into cells, and thus, reduce iobenguane efficacy. Discontinue interfering drugs for at least 5 half-lives before administration of either the dosimetry or an iobenguane dose. Do not administer these drugs until at least 7 days after each iobenguane dose.

            • isoflurane

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

            • levomilnacipran

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

            • lofepramine

              lofepramine, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

            • maprotiline

              maprotiline, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

            • methoxyflurane

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

            • methylergonovine

              methylergonovine, phentermine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.

            • milnacipran

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

            • nefazodone

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

            • nortriptyline

              nortriptyline, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

            • ozanimod

              ozanimod increases toxicity of phentermine 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.

            • paroxetine

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

            • protriptyline

              protriptyline, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

            • rasagiline

              rasagiline increases effects of phentermine by pharmacodynamic synergism. Avoid or Use Alternate Drug. Phentermine should not be administered during or within 14 days following the use of most MAOIs or drugs with MAO-inhibiting activity. Risk of acute hypertensive episode. .

            • selegiline

              selegiline increases effects of phentermine by pharmacodynamic synergism. Avoid or Use Alternate Drug. Phentermine should not be administered during or within 14 days following the use of most MAOIs or drugs with MAO-inhibiting activity. Risk of acute hypertensive episode. .

            • sertraline

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

            • sevoflurane

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

            • trazodone

              trazodone, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

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

            • trimipramine

              trimipramine, phentermine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.

            • venlafaxine

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

            • yohimbe

              yohimbe, phentermine. Mechanism: pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.

            Monitor Closely (162)

            • albuterol

              albuterol and phentermine both decrease sedation. Use Caution/Monitor.

              albuterol and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • alfentanil

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

            • alprazolam

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

            • amitriptyline

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

            • amobarbital

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

            • amoxapine

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

            • arformoterol

              arformoterol and phentermine both decrease sedation. Use Caution/Monitor.

              arformoterol and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • aripiprazole

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

            • armodafinil

              armodafinil and phentermine both decrease sedation. Use Caution/Monitor.

            • azelastine

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

            • belladonna and opium

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

            • benazepril

              phentermine decreases effects of benazepril by pharmacodynamic antagonism. Use Caution/Monitor.

            • benperidol

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

            • benzphetamine

              phentermine and benzphetamine both decrease sedation. Use Caution/Monitor.

              benzphetamine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • bromocriptine

              bromocriptine, phentermine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Hypertension, V tach.

            • brompheniramine

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

            • buprenorphine buccal

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

            • butabarbital

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

            • butalbital

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

            • butorphanol

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

            • caffeine

              caffeine and phentermine both decrease sedation. Use Caution/Monitor.

            • captopril

              phentermine decreases effects of captopril by pharmacodynamic antagonism. Use Caution/Monitor. Phentermine may decrease the antihypertensive effect of ACE Inhibitors.

            • carbinoxamine

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

            • chloral hydrate

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

            • chlordiazepoxide

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

            • chlorpheniramine

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

            • chlorpromazine

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

              chlorpromazine, phentermine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only.

            • cinnarizine

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

            • clemastine

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

            • clomipramine

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

            • clonazepam

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

            • clorazepate

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

            • clozapine

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

            • codeine

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

            • cyclizine

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

            • cyproheptadine

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

            • desipramine

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

            • dexchlorpheniramine

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

            • dexfenfluramine

              phentermine and dexfenfluramine both decrease sedation. Use Caution/Monitor.

              dexfenfluramine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • dexmedetomidine

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

            • dexmethylphenidate

              dexmethylphenidate and phentermine both decrease sedation. Use Caution/Monitor.

              dexmethylphenidate and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • dextroamphetamine

              dextroamphetamine and phentermine both decrease sedation. Use Caution/Monitor.

              dextroamphetamine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • dextromoramide

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

            • diamorphine

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

            • dichlorphenamide

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

            • diethylpropion

              phentermine and diethylpropion both decrease sedation. Use Caution/Monitor.

              diethylpropion and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • difenoxin hcl

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

            • diltiazem

              phentermine will decrease the level or effect of diltiazem by pharmacodynamic antagonism. Use Caution/Monitor. Amphetamines may diminish antihypertensive effects of diltiazem. Monitor BP.

            • dimenhydrinate

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

            • diphenhydramine

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

            • diphenoxylate hcl

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

            • dipipanone

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

            • dobutamine

              dobutamine and phentermine both decrease sedation. Use Caution/Monitor.

              dobutamine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • dopamine

              phentermine and dopamine both decrease sedation. Use Caution/Monitor.

              dopamine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • dopexamine

              dopexamine and phentermine both decrease sedation. Use Caution/Monitor.

              dopexamine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • doxepin

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

            • droperidol

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

            • droxidopa

              phentermine and droxidopa both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. May increase risk for supine hypertension

            • ephedrine

              ephedrine and phentermine both decrease sedation. Use Caution/Monitor.

              ephedrine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

              ephedrine, phentermine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor.

            • epinephrine

              epinephrine and phentermine both decrease sedation. Use Caution/Monitor.

              epinephrine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • epinephrine inhaled

              phentermine, epinephrine inhaled. Either increases effects of the other by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • epinephrine racemic

              epinephrine racemic and phentermine both decrease sedation. Use Caution/Monitor.

              epinephrine racemic and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • esketamine intranasal

              esketamine intranasal, phentermine. Either increases toxicity of the other by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. Closely monitor blood pressure with concomitant use of esketamine nasal with stimulants. .

            • estazolam

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

            • ethanol

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

            • fenfluramine

              phentermine and fenfluramine both decrease sedation. Use Caution/Monitor.

              fenfluramine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • fluphenazine

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

              fluphenazine, phentermine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only.

            • flurazepam

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

            • formoterol

              formoterol and phentermine both decrease sedation. Use Caution/Monitor.

              formoterol and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • green tea

              green tea, phentermine. Other (see comment). Use Caution/Monitor. Comment: Green tea may include caffeine. Caffeine is a CNS-stimulant and additive effects may be seen when coadministered with other CNS stimulants. Caffeine should be avoided or used cautiously.

            • haloperidol

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

            • hydralazine

              hydralazine, phentermine. Mechanism: pharmacodynamic antagonism. Use Caution/Monitor. Sympathomimetics can antagonize the activity of some antihypertensive agents.

            • hydromorphone

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

            • hydroxyzine

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

            • iloperidone

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

            • imipramine

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

            • ioflupane I 123

              phentermine decreases effects of ioflupane I 123 by receptor binding competition. Use Caution/Monitor. Drugs that bind to dopamine transporter receptor with high affinity may interfere with the image following ioflupane I 123 administration.

            • isoproterenol

              isoproterenol and phentermine both decrease sedation. Use Caution/Monitor.

              isoproterenol and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • ketotifen, ophthalmic

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

            • levalbuterol

              levalbuterol and phentermine both decrease sedation. Use Caution/Monitor.

              levalbuterol and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • levorphanol

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

            • lisdexamfetamine

              lisdexamfetamine and phentermine both decrease sedation. Use Caution/Monitor.

              lisdexamfetamine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • lofepramine

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

            • lofexidine

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

            • loprazolam

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

            • lorazepam

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

            • lormetazepam

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

            • loxapine

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

            • loxapine inhaled

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

            • maprotiline

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

            • marijuana

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

            • melatonin

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

            • meperidine

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

            • meprobamate

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

            • metaproterenol

              metaproterenol and phentermine both decrease sedation. Use Caution/Monitor.

              metaproterenol and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • metformin

              phentermine decreases effects of metformin by pharmacodynamic antagonism. Use Caution/Monitor. Patient should be closely observed for loss of blood glucose control; when drugs are withdrawn from a patient receiving metformin, patient should be observed closely for hypoglycemia.

            • methadone

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

            • methamphetamine

              methamphetamine and phentermine both decrease sedation. Use Caution/Monitor.

              methamphetamine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • methyldopa

              methyldopa increases effects of phentermine by unknown mechanism. Use Caution/Monitor.

            • methylenedioxymethamphetamine

              methylenedioxymethamphetamine and phentermine both decrease sedation. Use Caution/Monitor.

              methylenedioxymethamphetamine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • midazolam

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

            • midodrine

              phentermine and midodrine both decrease sedation. Use Caution/Monitor.

              midodrine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • mirtazapine

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

            • modafinil

              modafinil and phentermine both decrease sedation. Use Caution/Monitor.

            • morphine

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

            • motherwort

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

            • moxonidine

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

            • nabilone

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

            • nalbuphine

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

            • norepinephrine

              norepinephrine and phentermine both decrease sedation. Use Caution/Monitor.

              norepinephrine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • nortriptyline

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

            • olanzapine

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

            • opium tincture

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

            • oxazepam

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

            • oxycodone

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

            • oxymorphone

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

            • oxytocin

              oxytocin increases effects of phentermine by pharmacodynamic synergism. Use Caution/Monitor.

            • paliperidone

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

            • papaveretum

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

            • pentazocine

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

            • pentobarbital

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

            • perphenazine

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

              perphenazine, phentermine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only.

            • phendimetrazine

              phentermine and phendimetrazine both decrease sedation. Use Caution/Monitor.

              phendimetrazine and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • phenobarbital

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

            • phenylephrine

              phentermine and phenylephrine both decrease sedation. Use Caution/Monitor.

              phentermine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • phenylephrine PO

              phentermine and phenylephrine PO both decrease sedation. Use Caution/Monitor.

              phentermine and phenylephrine PO both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • pholcodine

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

            • pimozide

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

            • pirbuterol

              pirbuterol and phentermine both decrease sedation. Use Caution/Monitor.

              pirbuterol and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • primidone

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

            • prochlorperazine

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

              prochlorperazine, phentermine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only.

            • promazine

              promazine, phentermine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only.

            • promethazine

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

              promethazine, phentermine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only.

            • propylhexedrine

              phentermine and propylhexedrine both decrease sedation. Use Caution/Monitor.

              phentermine and propylhexedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • protriptyline

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

            • pseudoephedrine

              phentermine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • quazepam

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

            • quetiapine

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

            • risperidone

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

            • salmeterol

              salmeterol and phentermine both decrease sedation. Use Caution/Monitor.

              salmeterol and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • scullcap

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

            • secobarbital

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

            • shepherd's purse

              shepherd's purse increases and phentermine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

            • solriamfetol

              phentermine and solriamfetol both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • sufentanil

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

            • tapentadol

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

            • temazepam

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

            • terbutaline

              terbutaline and phentermine both decrease sedation. Use Caution/Monitor.

              terbutaline and phentermine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • thioridazine

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

              thioridazine, phentermine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only.

            • thiothixene

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

            • topiramate

              topiramate increases and phentermine decreases sedation. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.

            • tramadol

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

            • trazodone

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

            • triazolam

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

            • triclofos

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

            • trifluoperazine

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

              trifluoperazine, phentermine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only.

            • trimipramine

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

            • triprolidine

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

            • xylometazoline

              phentermine and xylometazoline both decrease sedation. Use Caution/Monitor.

              phentermine and xylometazoline both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • yohimbine

              phentermine and yohimbine both decrease sedation. Use Caution/Monitor.

              phentermine and yohimbine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.

            • ziconotide

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

            • ziprasidone

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

            Minor (7)

            • amantadine

              amantadine, phentermine. Either increases effects of the other by pharmacodynamic synergism. Minor/Significance Unknown. Potential for additive CNS stimulation.

            • American ginseng

              American ginseng increases effects of phentermine by pharmacodynamic synergism. Minor/Significance Unknown.

            • desmopressin

              desmopressin increases effects of phentermine by pharmacodynamic synergism. Minor/Significance Unknown.

            • eucalyptus

              eucalyptus increases and phentermine decreases sedation. Effect of interaction is not clear, use caution. Minor/Significance Unknown.

            • guarana

              guarana increases effects of phentermine by pharmacodynamic synergism. Minor/Significance Unknown.

            • sage

              sage increases and phentermine decreases sedation. Effect of interaction is not clear, use caution. Minor/Significance Unknown.

            • yerba mate

              yerba mate increases effects of phentermine by pharmacodynamic synergism. Minor/Significance Unknown.

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            Adverse Effects

            Frequency Not Defined

            Bad taste in mouth

            Blurred vision

            Changes in libido

            Chills

            Constipation

            Diarrhea

            Drug-induced GI disturbance

            Dry mouth

            Dysphoric mood

            Dysuria

            Excitement

            Hair loss

            Headache

            Hypertension

            Impotence

            Insomnia

            Myalgia

            Nausea

            Nervousness

            Palpitations

            Restlessness

            Tachycardia

            Tremor

            Urticaria

            Vomiting

            Serious

            • Heart valve disorder
            • Primary pulmonary hypertension
            • Psychotic disorder
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            Warnings

            Contraindications

            Known hypersensitivity or idiosyncratic reaction to sympathomimetic amines

            History of cardiovascular disease (coronary artery disease, uncontrolled hypertension, arrhythmias, stroke, congestive heart failure)

            Glaucoma

            Agitated states

            Hyperthyroidism

            History of drug abuse

            History of drug abuse

            Use of monoamine oxidase inhibitors (MAOIs) within preceding 14 days; concomitant administration of other CNS stimulants

            Pregnancy and breast feeding

            Cautions

            Primary pulmonary hypertension and valvular disease have been reported with therapy

            Avoid use of stimulants in patients with serious heart rhythm disturbances, cardiac abnormalities, cardiomyopathies, or other cardiac problems (see Contraindications)

            Caution in hypertension; risk of increase in blood pressure

            Patients with diabetes mellitus should use caution with antidiabetic agents like insulin or other hypoglycemic agents; dietary restrictions may lower requirements for antidiabetic therapy

            Drug has not been studied in renal impairment

            Use with caution in patients with seizure disorders or Tourette syndrome

            May impair ability to operate heavy machinery

            Concomitant administration with other weight-loss agents (eg, selective serotonin reuptake inhibitors [SSRIs], herbal preparations, other over-the-counter products) has not been studied

            Elderly are at high risk for myocardial infarction, hypertension, angina, or becoming dependent on phentermine with prolonged use

            Discontinue if weight loss has not occurred with 4 weeks of therapy

            Not approved for long-term use

            Discontinue if tolerance develops, and do not exceed recommended dosage to overcome tolerance

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            Pregnancy & Lactation

            Pregnancy category: X

            Lactation: Unknown if excreted in milk; contraindicated

            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

            Amphetamine-related anorexigenic agent; action in reducing appetite may be secondary to CNS effects that may involve stimulation of hypothalamus to release norepinephrine

            Absorption

            Peak plasma time: 3.0-4.4 hr (orally disintegrating tablet)

            Elimination

            Excretion: Urine (primarily)

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            Images

            BRAND FORM. UNIT PRICE PILL IMAGE
            Lomaira oral
            -
            8 mg tablet
            Adipex-P oral
            -
            37.5 mg capsule
            Adipex-P oral
            -
            37.5 mg tablet
            phentermine oral
            -
            37.5 mg tablet
            phentermine oral
            -
            15 mg capsule
            phentermine oral
            -
            30 mg capsule
            phentermine oral
            -
            37.5 mg capsule
            phentermine oral
            -
            37.5 mg tablet
            phentermine oral
            -
            15 mg capsule
            phentermine oral
            -
            37.5 mg tablet
            phentermine oral
            -
            30 mg capsule
            phentermine oral
            -
            30 mg capsule
            phentermine oral
            -
            30 mg capsule
            phentermine oral
            -
            30 mg capsule
            phentermine oral
            -
            37.5 mg capsule
            phentermine oral
            -
            37.5 mg tablet
            phentermine oral
            -
            30 mg capsule
            phentermine oral
            -
            37.5 mg capsule
            phentermine oral
            -
            15 mg capsule
            phentermine oral
            -
            30 mg capsule
            phentermine oral
            -
            30 mg capsule
            phentermine oral
            -
            15 mg capsule
            phentermine oral
            -
            30 mg capsule
            phentermine oral
            -
            37.5 mg tablet

            Copyright © 2010 First DataBank, Inc.

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            Patient Handout

            Patient Education
            phentermine oral

            PHENTERMINE - ORAL

            (FEN-ter-meen)

            COMMON BRAND NAME(S): Adipex-P, Ionamin, Pro-Fast

            USES: Phentermine is used with a doctor-approved exercise, behavior change, and reduced-calorie diet program to help you lose weight. It is used by certain overweight people, such as those who are obese or have weight-related medical problems. Losing weight and keeping it off can lessen the many health risks that come with obesity, including heart disease, diabetes, high blood pressure, and a shorter life.It is not known how this medication helps people to lose weight. It may work by decreasing your appetite, increasing the amount of energy used by your body, or by affecting certain parts of the brain. This medication is an appetite suppressant and belongs to a class of drugs called sympathomimetic amines.

            HOW TO USE: Take this medication by mouth as directed by your doctor, usually once a day, 1 hour before breakfast or 1 to 2 hours after breakfast. If needed, your doctor may adjust your dose to take a small dose up to 3 times a day. Carefully follow your doctor's instructions. Taking this medication late in the day may cause trouble sleeping (insomnia).If you are using sustained-release capsules, the dose is usually taken once a day before breakfast or at least 10 to 14 hours before bedtime. Swallow the medication whole. Do not crush or chew sustained-release capsules. Doing so can release all of the drug at once, increasing the risk of side effects.If you are using the tablets made to dissolve in the mouth, the dose is usually taken once a day in the morning, with or without food. First, dry your hands before handling the tablet. Place your dose on top of the tongue until it dissolves, then swallow it with or without water.The dosage and length of treatment are based on your medical condition and response to treatment. Your doctor will adjust the dose to find the best dose for you. Discuss the risks and benefits, and the length of phentermine treatment, with your doctor. To get the most benefit, take this medication regularly, exactly as prescribed, and for as long as directed by your doctor. To help you remember, take it at the same time(s) each day.If you suddenly stop using this medication, you may have withdrawal symptoms (such as depression, severe tiredness). To help prevent withdrawal, your doctor may lower your dose slowly. Withdrawal is more likely if you have used phentermine for a long time or in high doses. Tell your doctor or pharmacist right away if you have withdrawal.Though it helps many people, this medication may sometimes cause addiction. This risk may be higher if you have a substance use disorder (such as overuse of or addiction to drugs/alcohol). Do not increase your dose, take it more often, or use it for a longer time than prescribed. Properly stop the medication when so directed.This medication may stop working well after you have been taking it for a few weeks. Talk with your doctor if this medication stops working well. Do not increase the dose unless directed by your doctor. Your doctor may direct you to stop taking this medication.

            SIDE EFFECTS: Dizziness, dry mouth, difficulty sleeping, irritability, nausea, vomiting, diarrhea, or constipation may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.This medication may raise your blood pressure. Check your blood pressure regularly and tell your doctor if the results are high.Tell your doctor right away if you have any serious side effects, including: fast/irregular/pounding heartbeat, mental/mood changes (e.g., agitation, uncontrolled anger, hallucinations, nervousness), uncontrolled muscle movements, change in sexual ability/interest.Stop taking this medication and get medical help right away if you have any very serious side effects, including: severe headache, trouble speaking, seizure, weakness on one side of the body, vision changes (e.g., blurred vision).This drug may rarely cause serious (sometimes fatal) lung or heart problems (pulmonary hypertension, heart valve problems). The risk may increase with longer use of this medication and use of this drug along with other appetite-suppressant drugs/herbal products. Stop taking this medication and get medical help right away if you have any very serious side effects, including: chest pain, difficulty breathing with exercise, decreased ability to exercise, fainting, swelling of the legs/ankles/feet.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or 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: Before taking this medication, tell your doctor or pharmacist if you are allergic to it; or to any other sympathomimetic amines (including decongestants such as pseudoephedrine, stimulants such as amphetamine, appetite suppressants such as diethylpropion); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: diabetes, high blood pressure, glaucoma, personal or family history of a substance use disorder (such as overuse of or addiction to drugs/alcohol), heart disease (such as chest pain, heart attack, heart murmur, fast/irregular heartbeat, heart valve problems), mental/mood problems (such as depression, thoughts of suicide, severe anxiety/agitation), high blood pressure in the lungs (pulmonary hypertension), stroke, overactive thyroid (hyperthyroidism), kidney disease, seizures.This drug may make you dizzy or blur your vision. It may also rarely make you drowsy. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness or clear vision until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).If you have diabetes, check your blood sugar regularly as directed and share the results with your doctor. Your doctor may need to adjust your diabetes medication during treatment with this drug.If you are using the tablets made to dissolve in the mouth, your medication may contain aspartame. If you have phenylketonuria (PKU) or any other condition that requires you to limit/avoid aspartame (or phenylalanine) in your diet, ask your doctor or pharmacist about using this medication safely.Before having surgery, tell your doctor or dentist that you are using this medication.Kidney function declines as you grow older. This medication is removed by the kidneys. Therefore, elderly people may be at greater risk for dizziness and high blood pressure while using this drug.This medication must not be used during pregnancy. It may harm an unborn baby. If you are pregnant or think you may be pregnant, tell your doctor right away.This drug may pass into breast milk and could have undesirable effects on a nursing infant. Therefore, breast-feeding is not recommended while using this drug. Consult your doctor before breast-feeding.

            DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.This drug should not be used with certain medications because very serious interactions may occur. If you are taking or have taken other appetite-suppressant drugs in the past year (e.g., diethylpropion, ephedra/ma huang), tell your doctor or pharmacist before starting this medication.Taking MAO inhibitors with this medication may cause a serious (possibly fatal) drug interaction. Avoid taking MAO inhibitors (isocarboxazid, linezolid, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, safinamide, selegiline, tranylcypromine) during treatment with this medication. Most MAO inhibitors should also not be taken for two weeks before treatment with this medication. Ask your doctor when to start or stop taking this medication.Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially: high blood pressure medicine (such as guanethidine, methyldopa), phenothiazines (such as prochlorperazine, chlorpromazine), other stimulants (including amphetamines, methylphenidate, street drugs such as cocaine or MDMA/"ecstasy").Tell your doctor or pharmacist if you are taking other products that cause drowsiness such as opioid pain or cough relievers (such as codeine, hydrocodone), alcohol, marijuana (cannabis), drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine, diphenhydramine).Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.Some products have ingredients that could raise your heart rate or blood pressure. Tell your pharmacist what products you are using, and ask how to use them safely (especially cough-and-cold products or diet aids).Caffeine can increase the side effects of this medication. Avoid drinking large amounts of beverages containing caffeine (coffee, tea, colas) or eating large amounts of chocolate.This medication may interfere with certain medical/laboratory tests (including brain scan for Parkinson's disease), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.

            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. Symptoms of overdose may include: rapid breathing, unusual restlessness, fast/slow/irregular heartbeat, chest pain, hallucinations, seizures, loss of consciousness.

            NOTES: Appetite suppressants should not be used in place of proper diet. For best results, this drug must be used along with a doctor-approved diet and exercise program.Do not share this medication with others. Sharing it is against the law.Lab and/or medical tests (such as blood pressure, heart tests, kidney tests) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

            MISSED DOSE: If you miss a dose, take it as soon as you remember. If it is near the time of the next dose or late in the evening, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

            STORAGE: Store in a tightly closed container at room temperature away from light and moisture. Keep all medications away from children and pets.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 August 2020. Copyright(c) 2021 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.
            • Manage and view all your plans together – even plans in different states.
            • 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.