doxylamine/dextromethorphan (OTC)

Brand and Other Names:Vicks NyQuil Cough, Safetussin PM

Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

doxylamine/dextromethorphan

oral liquid

  • (6.25mg/15mg)/15mL

Cough, Rhinorrhea & Sneezing

30 mL PO q6hr; not to exceed 4 doses/day

Dosage Forms & Strengths

doxylamine/dextromethorphan

oral liquid

  • (6.25mg/15mg)/15mL

Cough, Rhinorrhea & Sneezing

<4 years: Do not use

4-12 years: Ask a pediatrician

>12 years: 30 mL PO q6hr; not to exceed 4 doses/day

Next:

Interactions

Interaction Checker

and doxylamine/dextromethorphan

No Results

     activity indicator 
    No Interactions Found
    Interactions Found

    Contraindicated

      Serious - Use Alternative

        Significant - Monitor Closely

          Minor

            All Interactions Sort By:
             activity indicator 

            Contraindicated (0)

              Serious - Use Alternative (17)

              • benzhydrocodone/acetaminophen

                benzhydrocodone/acetaminophen, doxylamine. 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.

              • calcium/magnesium/potassium/sodium oxybates

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

              • fentanyl

                fentanyl, doxylamine. 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, doxylamine. 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, doxylamine. 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, doxylamine. 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.

              • hydrocodone

                hydrocodone, doxylamine. 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.

              • isocarboxazid

                isocarboxazid increases effects of doxylamine by Other (see comment). Avoid or Use Alternate Drug. Comment: Isocarboxazid should not be administered in combination with antihistamines because of potential additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .

              • lemborexant

                lemborexant, doxylamine. Either increases effects of the other by sedation. Avoid or Use Alternate Drug. Use of lemborexant with other drugs to treat insomnia is not recommended.

              • methylene blue

                methylene blue and doxylamine both increase serotonin levels. Avoid or Use Alternate Drug. If drug combination must be administered, monitor for evidence of serotonergic or opioid-related toxicities

              • metoclopramide intranasal

                doxylamine, 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.

              • olopatadine intranasal

                doxylamine and olopatadine intranasal both increase sedation. Avoid or Use Alternate Drug. Coadministration increases risk of CNS depression, which can lead to additive impairment of psychomotor performance and cause daytime impairment.

              • selinexor

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

              • sodium oxybate

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

              • sufentanil SL

                sufentanil SL, doxylamine. 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.

              • tranylcypromine

                tranylcypromine increases effects of doxylamine by Other (see comment). Avoid or Use Alternate Drug. Comment: Tranylcypromine should not be administered in combination with antihistamines because of potential additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .

              • valerian

                valerian and doxylamine both increase sedation. Avoid or Use Alternate Drug.

              Monitor Closely (178)

              • acrivastine

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

              • alfentanil

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

              • alprazolam

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

              • amifampridine

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

              • amisulpride

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

              • amitriptyline

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

              • amobarbital

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

              • amoxapine

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

              • apomorphine

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

              • aripiprazole

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

              • asenapine

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

              • asenapine transdermal

                asenapine transdermal and doxylamine both increase sedation. Use Caution/Monitor.

              • avapritinib

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

              • azelastine

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

              • baclofen

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

              • belladonna and opium

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

              • benperidol

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

              • benzhydrocodone/acetaminophen

                benzhydrocodone/acetaminophen and doxylamine both increase sedation. Use Caution/Monitor.

              • benzphetamine

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

              • brexanolone

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

              • brexpiprazole

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

              • brimonidine

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

              • brivaracetam

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

              • brompheniramine

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

              • buprenorphine

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

              • buprenorphine buccal

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

              • buprenorphine subdermal implant

                buprenorphine subdermal implant and doxylamine both increase sedation. Use Caution/Monitor.

              • buprenorphine transdermal

                buprenorphine transdermal and doxylamine both increase sedation. Use Caution/Monitor.

              • buprenorphine, long-acting injection

                doxylamine 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.

                buprenorphine, long-acting injection and doxylamine both increase sedation. Use Caution/Monitor.

              • butabarbital

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

              • butalbital

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

              • butorphanol

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

              • carbinoxamine

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

              • carisoprodol

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

              • cenobamate

                cenobamate, doxylamine. Either increases effects of the other by sedation. Use Caution/Monitor.

              • chloral hydrate

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

              • chlordiazepoxide

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

              • chlorpheniramine

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

              • chlorpromazine

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

              • chlorzoxazone

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

              • cinnarizine

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

              • clemastine

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

              • clobazam

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

              • clomipramine

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

              • clonazepam

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

              • clonidine

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

              • clorazepate

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

              • clozapine

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

              • codeine

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

              • cyclizine

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

              • cyclobenzaprine

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

              • cyproheptadine

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

              • dantrolene

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

              • daridorexant

                doxylamine 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

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

              • deutetrabenazine

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

              • dexchlorpheniramine

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

              • dexfenfluramine

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

              • dexmedetomidine

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

              • dextromoramide

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

              • diamorphine

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

              • diazepam

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

              • diazepam intranasal

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

              • difelikefalin

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

              • difenoxin hcl

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

              • dimenhydrinate

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

              • diphenhydramine

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

              • diphenoxylate hcl

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

              • dipipanone

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

              • dopexamine

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

              • dosulepin

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

              • doxepin

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

              • droperidol

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

              • esketamine intranasal

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

              • estazolam

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

              • ethanol

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

              • etomidate

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

              • fenfluramine

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

              • flibanserin

                doxylamine and flibanserin both increase sedation. Modify Therapy/Monitor Closely. Risk for sedation increased if flibanserin is coadministration with other CNS depressants.

              • fluphenazine

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

              • flurazepam

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

              • gabapentin

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

              • gabapentin enacarbil

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

              • ganaxolone

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

              • gotu kola

                gotu kola increases effects of doxylamine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

              • haloperidol

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

              • hawthorn

                hawthorn increases effects of doxylamine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

              • hops

                hops increases effects of doxylamine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

              • hyaluronidase

                doxylamine decreases effects of hyaluronidase by Other (see comment). Use Caution/Monitor. Comment: Antihistamines, when given in large systemic doses, may render tissues partially resistant to the action of hyaluronidase. Patients may require larger amounts of hyaluronidase for equivalent dispersing effect. .

              • hydromorphone

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

              • hydroxyzine

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

              • iloperidone

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

              • imipramine

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

              • kava

                kava increases effects of doxylamine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

              • ketamine

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

              • ketotifen, ophthalmic

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

              • lasmiditan

                lasmiditan, doxylamine. 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.

              • levorphanol

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

              • lofepramine

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

              • lofexidine

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

              • loprazolam

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

              • lorazepam

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

              • lormetazepam

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

              • loxapine

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

              • loxapine inhaled

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

              • lurasidone

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

              • maprotiline

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

              • marijuana

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

              • melatonin

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

              • meperidine

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

              • meprobamate

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

              • metaxalone

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

              • methadone

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

              • methocarbamol

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

              • methylenedioxymethamphetamine

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

              • midazolam

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

              • midazolam intranasal

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

              • mirtazapine

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

              • morphine

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

              • motherwort

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

              • moxonidine

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

              • nabilone

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

              • nalbuphine

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

              • nortriptyline

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

              • olanzapine

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

              • oliceridine

                oliceridine, doxylamine. 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.

              • opium tincture

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

              • orphenadrine

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

              • oxazepam

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

              • oxycodone

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

              • oxymorphone

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

              • paliperidone

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

              • papaveretum

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

              • papaverine

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

              • passion flower

                passion flower increases effects of doxylamine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

              • pentazocine

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

              • pentobarbital

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

              • perphenazine

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

              • phenelzine

                phenelzine increases effects of doxylamine by Other (see comment). Modify Therapy/Monitor Closely. Comment: Coadministration of phenelzine and antihistamines may result in additive CNS depressant effects. MAO inhibitors also prolong and intensify anticholinergic effects of antihistamines. .

              • phenobarbital

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

              • phenylephrine PO

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

              • pholcodine

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

              • pimozide

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

              • pregabalin

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

              • primidone

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

              • prochlorperazine

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

              • promethazine

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

              • propofol

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

              • propylhexedrine

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

              • protriptyline

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

              • quazepam

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

              • quetiapine

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

              • ramelteon

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

              • remimazolam

                remimazolam, doxylamine. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely. Coadministration may result in profound sedation, respiratory depression, coma, and/or death. Continuously monitor vital signs during sedation and recovery period if coadministered. Carefully titrate remimazolam dose if administered with opioid analgesics and/or sedative/hypnotics.

              • risperidone

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

              • scullcap

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

              • secobarbital

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

              • sevoflurane

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

              • shepherd's purse

                doxylamine and shepherd's purse both increase sedation. Use Caution/Monitor.

              • stiripentol

                stiripentol, doxylamine. Either increases effects of the other by sedation. Use Caution/Monitor. Concomitant use stiripentol with other CNS depressants, including alcohol, may increase the risk of sedation and somnolence.

              • sufentanil

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

              • tapentadol

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

              • temazepam

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

              • thioridazine

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

              • thiothixene

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

              • topiramate

                doxylamine and topiramate both increase sedation. Modify Therapy/Monitor Closely.

              • tramadol

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

              • trazodone

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

              • triazolam

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

              • triclofos

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

              • trifluoperazine

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

              • trimipramine

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

              • triprolidine

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

              • valerian

                valerian increases effects of doxylamine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.

              • xylometazoline

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

              • ziconotide

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

              • ziprasidone

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

              • zotepine

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

              Minor (6)

              • ashwagandha

                ashwagandha increases effects of doxylamine by pharmacodynamic synergism. Minor/Significance Unknown. May enhance CNS depression.

              • brimonidine

                brimonidine increases effects of doxylamine by pharmacodynamic synergism. Minor/Significance Unknown. Increased CNS depression.

              • eucalyptus

                doxylamine and eucalyptus both increase sedation. Minor/Significance Unknown.

              • nettle

                nettle increases effects of doxylamine by pharmacodynamic synergism. Minor/Significance Unknown. (High dose nettle; theoretical interaction) May enhance CNS depression.

              • sage

                doxylamine and sage both increase sedation. Minor/Significance Unknown.

              • Siberian ginseng

                Siberian ginseng increases effects of doxylamine by pharmacodynamic synergism. Minor/Significance Unknown. May enhance CNS depression.

              Previous
              Next:

              Adverse Effects

              Common Adverse Effects

              Agranulocytosis

              Potential for abuse

              Leukopenia

              Serotonin syndrome

              Dizziness

              Drowsiness

              Thrombocytopenia

              Toxic psychosis

              GI disturbances

              Dry mouth, throat, and nose

              Thickening of mucus in nose or throat

              Constipation

              Blurred vision

              Headache

              Urinary retention

              Previous
              Next:

              Warnings

              Contraindications

              Hypersensitivity

              Asthma attacks

              Use of MAO inhibitors within 14 days

              < 2 years of age

              Narrow-angle glaucoma

              Breastfeeding

              Symptomatic prostate hypertrophy

              Bladder-neck obstruction

              Stenosing peptic ulcer

              Cautions

              Caution in patients < 6 years of age

              Doxylamine: Caution in used concomitantly with another CNS deppressatn; may exacerbate angle closure glaucoma, hyperthyroidism, peptic ulcer, or urinary tract obstruction; xerostomia may occur; caution in COPD, cardiovascular disease, asthma, increased intraocular pressure, elderly patients or GI obstruction

              Dextromethorphan: Do not take for persistent or chronic cough associated with smoking, asthma, or emphysema, or if it is accompanied by excessive phlegm unless directed by a healthcare provider; may decrease respiration rate

              Previous
              Next:

              Pregnancy & Lactation

              Pregnancy category: C

              Lactation: excreted in breast milk, use caution

              Pregnant or breastfeeding patients should seek advice of health professional before using OTC drugs

              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.

              Previous
              Next:

              Pharmacology

              Mechanism of Action

              Doxylamine: Competitively blocks histamine from binding to H1 receptors; significant antimuscarinic activity & penetrates CNS, which causes pronounced tendency to induce sedation

              Dextromethorphan: Cough suppressant that acts centrally on the cough center in medulla

              Previous
              Next:

              Images

              No images available for this drug.
              Previous
              Next:

              Patient Handout

              A Patient Handout is not currently available for this monograph.
              Previous
              Medscape prescription drug monographs are based on FDA-approved labeling information, unless otherwise noted, combined with additional data derived from primary medical literature.