How many mg is in one benadryl

diphenhydramine and aclidinium both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

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

diphenhydramine, amantadine. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Potential for increased anticholinergic adverse effects.

diphenhydramine 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.

diphenhydramine and amitriptyline both decrease cholinergic effects/transmission. Modify Therapy/Monitor Closely.diphenhydramine and amitriptyline both increase sedation. Use Caution/Monitor.

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

diphenhydramine and amoxapine both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and amoxapine both increase sedation. Use Caution/Monitor.

anticholinergic/sedative combos and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

diphenhydramine and aripiprazole both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of aripiprazole by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of aripiprazole by pharmacodynamic antagonism. Use Caution/Monitor.aripiprazole increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

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

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

atracurium and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.

atropine and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.

atropine IV/IM and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

belladonna alkaloids and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.

diphenhydramine and belladonna and opium both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and belladonna and opium both increase sedation. Use Caution/Monitor.

diphenhydramine and benperidol both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of benperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of benperidol by pharmacodynamic antagonism. Use Caution/Monitor.benperidol increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

diphenhydramine will increase the level or effect of benzhydrocodone/acetaminophen by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Hydromorphone (<3% of the circulating parent hydrocodone [benzhydrocodone is prodrug of hydrocodone]) is mainly formed by CYP2D6 mediated O-demethylation of hydrocodone. Hydromorphone may contribute to the total analgesic effect of hydrocodone.

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

benztropine and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor. Additive anticholinergic adverse effects may be seen with concurrent use.

bethanechol increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

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

diphenhydramine will increase the level or effect of brexpiprazole by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Administer a quarter of brexpiprazole dose if coadministered with a moderate CYP2D6 inhibitor PLUS a strong/moderate CYP3A4 inhibitor.

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

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

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

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

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

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

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

carbachol increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

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

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

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

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

cevimeline increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

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

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

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

diphenhydramine and chlorpromazine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of chlorpromazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of chlorpromazine by pharmacodynamic antagonism. Use Caution/Monitor.chlorpromazine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

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

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

cisatracurium and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

diphenhydramine will increase the level or effect of clomipramine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and clomipramine both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and clomipramine both increase sedation. Use Caution/Monitor.

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

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

diphenhydramine and clozapine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of clozapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of clozapine by pharmacodynamic antagonism. Use Caution/Monitor.clozapine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

diphenhydramine decreases effects of codeine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Prevents conversion of codeine to its active metabolite morphine.diphenhydramine and codeine both increase sedation. Use Caution/Monitor.

cyclizine and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.cyclizine and diphenhydramine both increase sedation. Use Caution/Monitor.

cyclobenzaprine and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and cyclobenzaprine both increase sedation. Use Caution/Monitor.

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

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

diphenhydramine 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.

darifenacin and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

diphenhydramine will increase the level or effect of desipramine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and desipramine both increase sedation. Use Caution/Monitor.

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

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

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

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

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

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

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

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

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

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

dicyclomine and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

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

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

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

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

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

donepezil increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

donepezil transdermal, diphenhydramine. Either decreases effects of the other by pharmacodynamic antagonism. Use Caution/Monitor.

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

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

diphenhydramine and dosulepin both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and dosulepin both increase sedation. Use Caution/Monitor.

diphenhydramine and doxepin both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and doxepin both increase sedation. Use Caution/Monitor.

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

diphenhydramine and droperidol both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of droperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of droperidol by pharmacodynamic antagonism. Use Caution/Monitor.droperidol increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

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

echothiophate iodide increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

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

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

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

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

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

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

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

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

fentanyl, diphenhydramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

fentanyl intranasal, diphenhydramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

fentanyl transdermal, diphenhydramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

fentanyl transmucosal, diphenhydramine. Either increases toxicity of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Coadministration of fentanyl with anticholinergics may increase risk for urinary retention and/or severe constipation, which may lead to paralytic ileus.

diphenhydramine and fesoterodine both decrease cholinergic effects/transmission. Use Caution/Monitor.

diphenhydramine and flavoxate both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

diphenhydramine and fluphenazine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of fluphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of fluphenazine by pharmacodynamic antagonism. Use Caution/Monitor.fluphenazine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

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

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

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

galantamine increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

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

diphenhydramine and glycopyrrolate both decrease cholinergic effects/transmission. Use Caution/Monitor.

diphenhydramine and glycopyrrolate inhaled both decrease cholinergic effects/transmission. Use Caution/Monitor.

glycopyrronium tosylate topical, diphenhydramine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration of glycopyrronium tosylate topical with other anticholinergic medications may result in additive anticholinergic adverse effects.

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

diphenhydramine will increase the level or effect of haloperidol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and haloperidol both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of haloperidol by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of haloperidol by pharmacodynamic antagonism. Use Caution/Monitor.haloperidol increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

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

diphenhydramine and henbane both decrease cholinergic effects/transmission. Use Caution/Monitor.

diphenhydramine and homatropine both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

huperzine A increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

diphenhydramine 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.

diphenhydramine will increase the level or effect of hydrocodone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Hydromorphone (<3% of the circulating parent hydrocodone) is mainly formed by CYP2D6 mediated O-demethylation of hydrocodone. Hydromorphone may contribute to the total analgesic effect of hydrocodone.

diphenhydramine will increase the level or effect of hydromorphone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and hydromorphone both increase sedation. Use Caution/Monitor.

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

diphenhydramine and hyoscyamine both decrease cholinergic effects/transmission. Use Caution/Monitor.

diphenhydramine and hyoscyamine spray both decrease cholinergic effects/transmission. Use Caution/Monitor.

diphenhydramine will increase the level or effect of iloperidone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and iloperidone both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of iloperidone by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of iloperidone by pharmacodynamic antagonism. Use Caution/Monitor.iloperidone increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

diphenhydramine will increase the level or effect of imipramine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and imipramine both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and imipramine both increase sedation. Use Caution/Monitor.

diphenhydramine and ipratropium both decrease cholinergic effects/transmission. Use Caution/Monitor. Due to the poor systemic absorption of ipratropium, interaction unlikely at regularly recommended dosages.

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

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

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

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

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

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

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

diphenhydramine, levodopa. Other (see comment). Use Caution/Monitor. Comment: Anticholinergic agents may enhance the therapeutic effects of levodopa; however, anticholinergic agents can exacerbate tardive dyskinesia. In high dosage, anticholinergics may decrease the effects of levodopa by delaying its GI absorption. .

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

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

diphenhydramine will increase the level or effect of lofepramine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and lofepramine both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and lofepramine both increase sedation. Use Caution/Monitor.

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

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

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

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

diphenhydramine and loxapine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of loxapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of loxapine by pharmacodynamic antagonism. Use Caution/Monitor.loxapine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

loxapine inhaled increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.diphenhydramine and loxapine inhaled both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of loxapine inhaled by pharmacodynamic antagonism. Use Caution/Monitor.

lurasidone, diphenhydramine. 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.

diphenhydramine and maprotiline both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and maprotiline both increase sedation. Use Caution/Monitor.

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

diphenhydramine and meclizine both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

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

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

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

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

diphenhydramine will increase the level or effect of methamphetamine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine increases and methamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.

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

diphenhydramine and methscopolamine both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

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

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

midazolam intranasal, diphenhydramine. 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.

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

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

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

diphenhydramine will increase the level or effect of morphine by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and morphine both increase sedation. Use Caution/Monitor.

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

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

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

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

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

neostigmine increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

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

diphenhydramine will increase the level or effect of nortriptyline by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and nortriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and nortriptyline both increase sedation. Use Caution/Monitor.

diphenhydramine and olanzapine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of olanzapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of olanzapine by pharmacodynamic antagonism. Use Caution/Monitor.olanzapine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

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

onabotulinumtoxinA and diphenhydramine both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

diphenhydramine and orphenadrine both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and orphenadrine both increase sedation. Use Caution/Monitor.

diphenhydramine, ospemifene. Either increases levels of the other by plasma protein binding competition. Modify Therapy/Monitor Closely.

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

diphenhydramine and oxybutynin both decrease cholinergic effects/transmission. Use Caution/Monitor.

diphenhydramine and oxybutynin topical both decrease cholinergic effects/transmission. Use Caution/Monitor.

diphenhydramine and oxybutynin transdermal both decrease cholinergic effects/transmission. Use Caution/Monitor.

diphenhydramine will increase the level or effect of oxycodone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and oxycodone both increase sedation. Use Caution/Monitor.

diphenhydramine will increase the level or effect of oxymorphone by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.diphenhydramine and oxymorphone both increase sedation. Use Caution/Monitor.

diphenhydramine and paliperidone both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of paliperidone by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of paliperidone by pharmacodynamic antagonism. Use Caution/Monitor.paliperidone increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

diphenhydramine and pancuronium both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

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

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

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

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

diphenhydramine and perphenazine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of perphenazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of perphenazine by pharmacodynamic antagonism. Use Caution/Monitor.perphenazine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

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

phenelzine increases effects of diphenhydramine 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. .

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

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

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

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

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

physostigmine increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

pilocarpine increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

diphenhydramine and pimozide both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of pimozide by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of pimozide by pharmacodynamic antagonism. Use Caution/Monitor.pimozide increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

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

diphenhydramine and pralidoxime both decrease cholinergic effects/transmission. Use Caution/Monitor.

pregabalin, diphenhydramine. 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.

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

diphenhydramine and prochlorperazine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of prochlorperazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of prochlorperazine by pharmacodynamic antagonism. Use Caution/Monitor.prochlorperazine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

diphenhydramine and promethazine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of promethazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of promethazine by pharmacodynamic antagonism. Use Caution/Monitor.promethazine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

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

diphenhydramine and propantheline both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

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

diphenhydramine and protriptyline both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and protriptyline both increase sedation. Use Caution/Monitor.

pyridostigmine increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

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

diphenhydramine and quetiapine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of quetiapine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of quetiapine by pharmacodynamic antagonism. Use Caution/Monitor.quetiapine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

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

diphenhydramine and rapacuronium both decrease cholinergic effects/transmission. Use Caution/Monitor.

diphenhydramine and risperidone both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of risperidone by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of risperidone by pharmacodynamic antagonism. Use Caution/Monitor.risperidone increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

diphenhydramine and rocuronium both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

diphenhydramine and scopolamine both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

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

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

diphenhydramine and solifenacin both decrease cholinergic effects/transmission. Use Caution/Monitor.

stiripentol, diphenhydramine. 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.

succinylcholine increases and diphenhydramine decreases cholinergic effects/transmission. Effect of interaction is not clear, use caution. Use Caution/Monitor.

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

diphenhydramine decreases effects of tamoxifen by decreasing metabolism. Use Caution/Monitor. Inhibition of CYP2D6 metabolism to tamoxifen's active metabolite, endoxifen.

diphenhydramine increases levels of tamsulosin by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.

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

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

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

diphenhydramine and thioridazine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of thioridazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of thioridazine by pharmacodynamic antagonism. Use Caution/Monitor.thioridazine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

diphenhydramine and thiothixene both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of thiothixene by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of thiothixene by pharmacodynamic antagonism. Use Caution/Monitor.thiothixene increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

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

diphenhydramine and tiotropium both decrease cholinergic effects/transmission. Use Caution/Monitor.

diphenhydramine and tolterodine both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

diphenhydramine decreases effects of tramadol by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Decreased conversion of tramadol to active metabolite.diphenhydramine and tramadol both increase sedation. Use Caution/Monitor.diphenhydramine decreases effects of tramadol by decreasing metabolism. Use Caution/Monitor. Decreased conversion of tramadol to active metabolite.

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

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

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

diphenhydramine and trifluoperazine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of trifluoperazine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of trifluoperazine by pharmacodynamic antagonism. Use Caution/Monitor.trifluoperazine increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

diphenhydramine and trihexyphenidyl both decrease cholinergic effects/transmission. Use Caution/Monitor. Potential for additive anticholinergic effects.

diphenhydramine and trimipramine both decrease cholinergic effects/transmission. Use Caution/Monitor.diphenhydramine and trimipramine both increase sedation. Use Caution/Monitor.

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

diphenhydramine and trospium chloride both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

diphenhydramine and vecuronium both decrease cholinergic effects/transmission. Use Caution/Monitor.

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

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

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

diphenhydramine and ziprasidone both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of ziprasidone by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of ziprasidone by pharmacodynamic antagonism. Use Caution/Monitor.ziprasidone increases effects of diphenhydramine by pharmacodynamic synergism. Use Caution/Monitor. Additive anticholinergic effects, possible hypoglycemia.

diphenhydramine and zotepine both increase sedation. Use Caution/Monitor.diphenhydramine decreases levels of zotepine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.diphenhydramine decreases levels of zotepine by pharmacodynamic antagonism. Use Caution/Monitor.