Dosing & Uses
Dosage Forms & Strengths
brompheniramine/dextromethorphan/phenylephrine
oral solution
- (1mg/5mg/2.5mg)/5mL
Relief of Cold Symptoms
4 teaspoons (20 mL) PO q4hr; not to exceed 120 mL/24 hr
Dosage Forms & Strengths
brompheniramine/dextromethorphan/phenylephrine
oral solution
- (1mg/5mg/2.5mg)/5mL
Relief of Cold Symptoms
<6 years
- Not recommended
6-12 years
- 2 teaspoons (10 mL) PO q4hr
>12 years
- 4 teaspoons (20 mL) PO q4hr
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Contraindicated (11)
- iobenguane I 123
phenylephrine 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 and dextromethorphan both increase serotonin levels. Contraindicated.
isocarboxazid increases effects of phenylephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode. - linezolid
linezolid increases effects of phenylephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- phenelzine
phenelzine and dextromethorphan both increase serotonin levels. Contraindicated.
- phenelzine
phenelzine increases effects of phenylephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- procarbazine
procarbazine increases effects of phenylephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
procarbazine and dextromethorphan both increase serotonin levels. Contraindicated. Combination is contraindicated within 2 weeks of MAOI use. - rasagiline
rasagiline and dextromethorphan both increase serotonin levels. Contraindicated. Risk of psychosis episodes or bizarre behavior.
- selegiline transdermal
selegiline transdermal increases effects of phenylephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- safinamide
dextromethorphan, safinamide. Other (see comment). Contraindicated. Comment: Coadministration of MAOIs and dextromethorphan has been reported to cause episodes of psychosis or bizarre behavior.
- selegiline
selegiline and dextromethorphan both increase serotonin levels. Contraindicated.
- tranylcypromine
tranylcypromine and dextromethorphan both increase serotonin levels. Contraindicated.
tranylcypromine increases effects of phenylephrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
Serious - Use Alternative (59)
- amitriptyline
amitriptyline and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
amitriptyline, phenylephrine. 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 and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
amoxapine, phenylephrine. 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. - buspirone
buspirone and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
- cabergoline
cabergoline, phenylephrine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.
- calcium/magnesium/potassium/sodium oxybates
brompheniramine, 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.
- citalopram
citalopram and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug. Combination may increase risk of serotonin syndrome or neuroleptic malignant syndrome-like reactions.
- clomipramine
clomipramine and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
clomipramine, phenylephrine. 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 phenylephrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.
desflurane increases levels of phenylephrine by decreasing metabolism. Contraindicated. - desipramine
desipramine and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
- desipramine
desipramine, phenylephrine. 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.
- desvenlafaxine
dextromethorphan and desvenlafaxine both increase serotonin levels. Avoid or Use Alternate Drug.
- dihydroergotamine
dihydroergotamine, phenylephrine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.
- dihydroergotamine intranasal
dihydroergotamine intranasal, phenylephrine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.
- doxapram
doxapram increases effects of phenylephrine by pharmacodynamic synergism. Avoid or Use Alternate Drug. Additive pressor effect.
- doxepin
doxepin and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
doxepin, phenylephrine. 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 will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.
duloxetine and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug. - eluxadoline
brompheniramine, eluxadoline. Either increases effects of the other by pharmacodynamic synergism. Avoid or Use Alternate Drug. Avoid coadministration with other drugs that cause constipation. Increases risk for constipation related serious adverse reactions.
- ergoloid mesylates
ergoloid mesylates, phenylephrine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.
- ergotamine
ergotamine, phenylephrine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.
- escitalopram
escitalopram and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
- ether
ether increases toxicity of phenylephrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.
- etomidate
etomidate increases levels of phenylephrine by decreasing metabolism. Contraindicated.
- fluoxetine
fluoxetine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.
fluoxetine and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug. - fluvoxamine
fluvoxamine and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
- grapefruit
grapefruit will increase the level or effect of dextromethorphan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- imipramine
imipramine and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
imipramine, phenylephrine. 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. - isocarboxazid
isocarboxazid increases effects of brompheniramine 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. .
- levomilnacipran
levomilnacipran and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
- isoflurane
isoflurane increases toxicity of phenylephrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.
- linezolid
linezolid and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug. Linezolid may increase serotonin as a result of MAO-A inhibition. If linezolid must be administered, discontinue serotonergic drug immediately and monitor for CNS toxicity. Serotonergic therapy may be resumed 24 hours after last linezolid dose or after 2 weeks of monitoring, whichever comes first.
- lofepramine
lofepramine, phenylephrine. 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.
lofepramine and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug. - lorcaserin
dextromethorphan and lorcaserin both increase serotonin levels. Avoid or Use Alternate Drug.
- maprotiline
maprotiline, phenylephrine. 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 and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
- memantine
memantine, dextromethorphan. Either increases toxicity of the other by pharmacodynamic synergism. Contraindicated.
- meperidine
dextromethorphan and meperidine both increase serotonin levels. Avoid or Use Alternate Drug.
- methoxyflurane
methoxyflurane increases toxicity of phenylephrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.
- methylene blue
methylene blue and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug. Methylene blue may increase serotonin as a result of MAO-A inhibition. If methylene blue must be administered, discontinue serotonergic drug immediately and monitor for CNS toxicity. Serotonergic therapy may be resumed 24 hours after last methylene blue dose or after 2 weeks of monitoring, whichever comes first.
- methylergonovine
methylergonovine, phenylephrine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.
- metoclopramide intranasal
brompheniramine, 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.
- milnacipran
milnacipran and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
- nefazodone
nefazodone and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
- nortriptyline
nortriptyline and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
nortriptyline, phenylephrine. 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. - olopatadine intranasal
brompheniramine 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.
- paroxetine
paroxetine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.
paroxetine and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug. - pitolisant
brompheniramine decreases effects of pitolisant by Other (see comment). Avoid or Use Alternate Drug. Comment: Pitolisant increases histamine levels in the brain; therefore, H1 receptor antagonists that cross the blood-brain barrier may reduce the efficacy of pitolisant.
- propofol
propofol increases levels of phenylephrine by decreasing metabolism. Contraindicated.
- protriptyline
protriptyline, phenylephrine. 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.
protriptyline and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug. - selegiline transdermal
selegiline transdermal and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
- selinexor
selinexor, brompheniramine. unspecified interaction mechanism. Avoid or Use Alternate Drug. Patients treated with selinexor may experience neurological toxicities. Avoid taking selinexor with other medications that may cause dizziness or confusion.
- sertraline
sertraline and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
- St John's Wort
dextromethorphan and St John's Wort both increase serotonin levels. Avoid or Use Alternate Drug.
- sevoflurane
sevoflurane increases toxicity of phenylephrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.
sevoflurane increases levels of phenylephrine by decreasing metabolism. Contraindicated. - sodium oxybate
brompheniramine, 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.
- tranylcypromine
tranylcypromine increases effects of brompheniramine 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. .
- trazodone
trazodone and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
trazodone, phenylephrine. 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. - trimipramine
trimipramine and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug.
- venlafaxine
venlafaxine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Avoid or Use Alternate Drug.
venlafaxine and dextromethorphan both increase serotonin levels. Avoid or Use Alternate Drug. - vilazodone
dextromethorphan, vilazodone. Either increases toxicity of the other by serotonin levels. Avoid or Use Alternate Drug. Concomitant therapy should be discontinued immediately if signs or symptoms of serotonin syndrome emerge and supportive symptomatic treatment should be initiated. .
Monitor Closely (315)
- 5-HTP
5-HTP and dextromethorphan both increase serotonin levels. Modify Therapy/Monitor Closely.
- abiraterone
abiraterone increases levels of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Avoid coadministration of abiraterone with substrates of CYP2D6. If alternative therapy cannot be used, exercise caution and consider a dose reduction of the CYP2D6 substrate.
- acrivastine
acrivastine and brompheniramine both increase sedation. Use Caution/Monitor.
- albuterol
albuterol and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
albuterol and phenylephrine both decrease sedation. Use Caution/Monitor.
brompheniramine increases and albuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - alfentanil
brompheniramine and alfentanil both increase sedation. Use Caution/Monitor.
alfentanil increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - almotriptan
almotriptan and dextromethorphan both increase serotonin levels. Modify Therapy/Monitor Closely.
- alprazolam
brompheniramine and alprazolam both increase sedation. Use Caution/Monitor.
alprazolam increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - amifampridine
brompheniramine 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.
- amitriptyline
amitriptyline increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- amisulpride
amisulpride and brompheniramine both increase sedation. Use Caution/Monitor.
- amitriptyline
brompheniramine and amitriptyline both increase sedation. Use Caution/Monitor.
- amobarbital
amobarbital increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and amobarbital both increase sedation. Use Caution/Monitor. - amoxapine
amoxapine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and amoxapine both increase sedation. Use Caution/Monitor. - amphetamine
amphetamine, dextromethorphan. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when amphemtamines are coadministered with dextromethorphan. .
- apomorphine
brompheniramine and apomorphine both increase sedation. Use Caution/Monitor.
- arformoterol
arformoterol and phenylephrine both decrease sedation. Use Caution/Monitor.
arformoterol and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - arformoterol
brompheniramine increases and arformoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- aripiprazole
aripiprazole increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
dextromethorphan, aripiprazole. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
brompheniramine and aripiprazole both increase sedation. Use Caution/Monitor. - armodafinil
brompheniramine increases and armodafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
armodafinil and phenylephrine both decrease sedation. Use Caution/Monitor. - artemether/lumefantrine
artemether/lumefantrine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.
- asenapine
dextromethorphan, asenapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
asenapine and brompheniramine both increase sedation. Use Caution/Monitor. - atomoxetine
atomoxetine, phenylephrine. Other (see comment). Use Caution/Monitor. Comment: Due to the potential for increases in blood pressure and heart rate, atomoxetine should be used cautiously with vasopressors such as phenylephrine.
- bupropion
bupropion will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.
- asenapine transdermal
asenapine transdermal and brompheniramine both increase sedation. Use Caution/Monitor.
- avapritinib
avapritinib and brompheniramine both increase sedation. Use Caution/Monitor.
- azelastine
azelastine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
azelastine and brompheniramine both increase sedation. Use Caution/Monitor. - baclofen
brompheniramine and baclofen both increase sedation. Use Caution/Monitor.
- belladonna and opium
belladonna and opium increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- belladonna and opium
brompheniramine and belladonna and opium both increase sedation. Use Caution/Monitor.
- benperidol
brompheniramine and benperidol both increase sedation. Use Caution/Monitor.
benperidol increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - benzhydrocodone/acetaminophen
benzhydrocodone/acetaminophen and brompheniramine both increase sedation. Use Caution/Monitor.
- benzphetamine
benzphetamine and phenylephrine both decrease sedation. Use Caution/Monitor.
benzphetamine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - benzphetamine
brompheniramine increases and benzphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- brexanolone
brexanolone, brompheniramine. Either increases toxicity of the other by sedation. Use Caution/Monitor.
- brexpiprazole
brexpiprazole and brompheniramine both increase sedation. Use Caution/Monitor.
- brimonidine
brimonidine and brompheniramine both increase sedation. Use Caution/Monitor.
- brivaracetam
brivaracetam and brompheniramine both increase sedation. Use Caution/Monitor.
- bromocriptine
bromocriptine, phenylephrine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Hypertension, V tach.
- brompheniramine
brompheniramine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- buprenorphine
brompheniramine and buprenorphine both increase sedation. Use Caution/Monitor.
- buprenorphine buccal
brompheniramine and buprenorphine buccal both increase sedation. Use Caution/Monitor.
buprenorphine buccal increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - buprenorphine subdermal implant
buprenorphine subdermal implant and brompheniramine both increase sedation. Use Caution/Monitor.
- butabarbital
butabarbital increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- butabarbital
brompheniramine and butabarbital both increase sedation. Use Caution/Monitor.
- butalbital
butalbital increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and butalbital both increase sedation. Use Caution/Monitor. - butorphanol
brompheniramine and butorphanol both increase sedation. Use Caution/Monitor.
butorphanol increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - caffeine
brompheniramine increases and caffeine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
caffeine and phenylephrine both decrease sedation. Use Caution/Monitor. - carbinoxamine
brompheniramine and carbinoxamine both increase sedation. Use Caution/Monitor.
carbinoxamine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - cariprazine
dextromethorphan, cariprazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- carisoprodol
brompheniramine and carisoprodol both increase sedation. Use Caution/Monitor.
- chloral hydrate
chloral hydrate increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- cenobamate
cenobamate, brompheniramine. Either increases effects of the other by sedation. Use Caution/Monitor.
- chloral hydrate
brompheniramine and chloral hydrate both increase sedation. Use Caution/Monitor.
- chlordiazepoxide
chlordiazepoxide increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and chlordiazepoxide both increase sedation. Use Caution/Monitor. - chlorpheniramine
chlorpheniramine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and chlorpheniramine both increase sedation. Use Caution/Monitor. - chlorpromazine
chlorpromazine, phenylephrine. 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.
chlorpromazine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and chlorpromazine both increase sedation. Use Caution/Monitor. - chlorzoxazone
brompheniramine and chlorzoxazone both increase sedation. Use Caution/Monitor.
- cinnarizine
cinnarizine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- cinnarizine
brompheniramine and cinnarizine both increase sedation. Use Caution/Monitor.
- clemastine
brompheniramine and clemastine both increase sedation. Use Caution/Monitor.
clemastine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - clobazam
brompheniramine, clobazam. Other (see comment). Use Caution/Monitor. Comment: Concomitant administration can increase the potential for CNS effects (e.g., increased sedation or respiratory depression).
clobazam will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Lower doses of drugs metabolized by CYP2D6 may be required when used concomitantly. - clomipramine
clomipramine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- clozapine
dextromethorphan, clozapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- clomipramine
brompheniramine and clomipramine both increase sedation. Use Caution/Monitor.
- clonazepam
brompheniramine and clonazepam both increase sedation. Use Caution/Monitor.
clonazepam increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - clorazepate
brompheniramine and clorazepate both increase sedation. Use Caution/Monitor.
clorazepate increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - clozapine
clozapine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and clozapine both increase sedation. Use Caution/Monitor. - cocaine topical
cocaine topical and dextromethorphan both increase serotonin levels. Modify Therapy/Monitor Closely.
- codeine
codeine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and codeine both increase sedation. Use Caution/Monitor. - cyclizine
brompheniramine and cyclizine both increase sedation. Use Caution/Monitor.
cyclizine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - cyclobenzaprine
brompheniramine and cyclobenzaprine both increase sedation. Use Caution/Monitor.
- cyproheptadine
cyproheptadine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- cyproheptadine
brompheniramine and cyproheptadine both increase sedation. Use Caution/Monitor.
- dantrolene
brompheniramine and dantrolene both increase sedation. Use Caution/Monitor.
- daridorexant
brompheniramine 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.
- desflurane
desflurane and brompheniramine both increase sedation. Use Caution/Monitor.
- desipramine
desipramine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and desipramine both increase sedation. Use Caution/Monitor. - desvenlafaxine
desvenlafaxine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Desvenlafaxine inhibits CYP2D6; with higher desvenlafaxine doses (ie, 400 mg) decrease the CYP2D6 substrate dose by up to 50%; no dosage adjustment needed with desvenlafaxine doses <100 mg
- deutetrabenazine
brompheniramine and deutetrabenazine both increase sedation. Use Caution/Monitor.
- dexchlorpheniramine
dexchlorpheniramine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- dexchlorpheniramine
brompheniramine and dexchlorpheniramine both increase sedation. Use Caution/Monitor.
- dexfenfluramine
dexfenfluramine and dextromethorphan both increase serotonin levels. Modify Therapy/Monitor Closely.
dexfenfluramine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
dexfenfluramine and phenylephrine both decrease sedation. Use Caution/Monitor.
brompheniramine increases and dexfenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - dexmedetomidine
brompheniramine and dexmedetomidine both increase sedation. Use Caution/Monitor.
dexmedetomidine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - dextroamphetamine
dextroamphetamine, dextromethorphan. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when amphemtamines are coadministered with dextromethorphan. .
- dexmethylphenidate
brompheniramine increases and dexmethylphenidate decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
dexmethylphenidate and phenylephrine both decrease sedation. Use Caution/Monitor.
dexmethylphenidate and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - dextroamphetamine
dextroamphetamine and phenylephrine both decrease sedation. Use Caution/Monitor.
brompheniramine increases and dextroamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
dextroamphetamine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - dextroamphetamine transdermal
dextromethorphan, dextroamphetamine transdermal. Either increases effects of the other by serotonin levels. Modify Therapy/Monitor Closely. Initiate with lower doses and monitor for signs and symptoms of serotonin syndrome, particularly during initiation or dosage increase. If serotonin syndrome occurs, discontinue dextroamphetamine transdermal and concomitant serotonergic drug(s).
dextroamphetamine transdermal, dextromethorphan. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when amphemtamines are coadministered with dextromethorphan. . - dextromoramide
brompheniramine and dextromoramide both increase sedation. Use Caution/Monitor.
dextromoramide increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - diamorphine
brompheniramine and diamorphine both increase sedation. Use Caution/Monitor.
diamorphine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - diazepam
brompheniramine and diazepam both increase sedation. Use Caution/Monitor.
- diethylpropion
diethylpropion and phenylephrine both decrease sedation. Use Caution/Monitor.
diethylpropion and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - diazepam intranasal
diazepam intranasal, brompheniramine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration may potentiate the CNS-depressant effects of each drug.
- diethylpropion
brompheniramine increases and diethylpropion decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- difelikefalin
difelikefalin and brompheniramine both increase sedation. Use Caution/Monitor.
- difenoxin hcl
difenoxin hcl increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and difenoxin hcl both increase sedation. Use Caution/Monitor. - dihydroergotamine
dextromethorphan and dihydroergotamine both increase serotonin levels. Modify Therapy/Monitor Closely.
- dihydroergotamine intranasal
dextromethorphan and dihydroergotamine intranasal both increase serotonin levels. Modify Therapy/Monitor Closely.
- dimenhydrinate
dimenhydrinate increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and dimenhydrinate both increase sedation. Use Caution/Monitor. - diphenhydramine
brompheniramine and diphenhydramine both increase sedation. Use Caution/Monitor.
diphenhydramine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - diphenoxylate hcl
brompheniramine and diphenoxylate hcl both increase sedation. Use Caution/Monitor.
diphenoxylate hcl increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - dipipanone
dipipanone increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and dipipanone both increase sedation. Use Caution/Monitor. - dobutamine
brompheniramine increases and dobutamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
dobutamine and phenylephrine both decrease sedation. Use Caution/Monitor.
dobutamine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - donepezil transdermal
donepezil transdermal, brompheniramine. Either decreases effects of the other by pharmacodynamic antagonism. Use Caution/Monitor.
- dopamine
dopamine and phenylephrine both decrease sedation. Use Caution/Monitor.
dopamine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - dopamine
brompheniramine increases and dopamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- dopexamine
brompheniramine increases and dopexamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
dopexamine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
dopexamine and phenylephrine both decrease sedation. Use Caution/Monitor. - dosulepin
brompheniramine and dosulepin both increase sedation. Use Caution/Monitor.
- doxepin
doxepin increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- doxepin
brompheniramine and doxepin both increase sedation. Use Caution/Monitor.
- doxylamine
brompheniramine and doxylamine both increase sedation. Use Caution/Monitor.
- droperidol
brompheniramine and droperidol both increase sedation. Use Caution/Monitor.
droperidol increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - droxidopa
phenylephrine and droxidopa both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. May increase risk for supine hypertension
- eletriptan
eletriptan and dextromethorphan both increase serotonin levels. Modify Therapy/Monitor Closely.
- ephedrine
brompheniramine increases and ephedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- ephedrine
ephedrine and phenylephrine both decrease sedation. Use Caution/Monitor.
ephedrine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
ephedrine, phenylephrine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. - epinephrine
epinephrine and phenylephrine both decrease sedation. Use Caution/Monitor.
epinephrine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
brompheniramine increases and epinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - epinephrine inhaled
phenylephrine, epinephrine inhaled. Either increases effects of the other by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- epinephrine racemic
brompheniramine increases and epinephrine racemic decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- epinephrine racemic
epinephrine racemic and phenylephrine both decrease sedation. Use Caution/Monitor.
epinephrine racemic and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - ergotamine
dextromethorphan and ergotamine both increase serotonin levels. Modify Therapy/Monitor Closely.
- esketamine intranasal
esketamine intranasal, brompheniramine. Either increases toxicity of the other by sedation. Modify Therapy/Monitor Closely.
- estazolam
estazolam increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and estazolam both increase sedation. Use Caution/Monitor. - ethanol
brompheniramine and ethanol both increase sedation. Use Caution/Monitor.
ethanol increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - etomidate
etomidate and brompheniramine both increase sedation. Use Caution/Monitor.
- fenfluramine
fenfluramine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
fenfluramine, dextromethorphan. Either increases effects of the other by serotonin levels. Use Caution/Monitor. Coadministration with drugs that increase serotoninergic effects may increase the risk of serotonin syndrome.
dextromethorphan and fenfluramine both increase serotonin levels. Modify Therapy/Monitor Closely.
fenfluramine and phenylephrine both decrease sedation. Use Caution/Monitor. - fenfluramine
brompheniramine increases and fenfluramine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- fluphenazine
dextromethorphan, fluphenazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- fentanyl
fentanyl, brompheniramine. 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
fentanyl intranasal, brompheniramine. 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
fentanyl transdermal, brompheniramine. 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
fentanyl transmucosal, brompheniramine. 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.
- flibanserin
brompheniramine and flibanserin both increase sedation. Modify Therapy/Monitor Closely. Risk for sedation increased if flibanserin is coadministration with other CNS depressants.
- fluphenazine
fluphenazine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and fluphenazine both increase sedation. Use Caution/Monitor.
fluphenazine, phenylephrine. 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 phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and flurazepam both increase sedation. Use Caution/Monitor. - formoterol
formoterol and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
brompheniramine increases and formoterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
formoterol and phenylephrine both decrease sedation. Use Caution/Monitor. - frovatriptan
frovatriptan and dextromethorphan both increase serotonin levels. Modify Therapy/Monitor Closely.
- gabapentin
gabapentin, brompheniramine. 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.
- haloperidol
haloperidol increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
dextromethorphan, haloperidol. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction). - gabapentin enacarbil
gabapentin enacarbil, brompheniramine. 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.
- iloperidone
dextromethorphan, iloperidone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- ganaxolone
brompheniramine and ganaxolone both increase sedation. Use Caution/Monitor.
- glycopyrronium tosylate topical
glycopyrronium tosylate topical, brompheniramine. 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
gotu kola increases effects of brompheniramine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.
- haloperidol
brompheniramine and haloperidol both increase sedation. Use Caution/Monitor.
- hawthorn
hawthorn increases effects of brompheniramine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.
- hops
hops increases effects of brompheniramine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.
- hyaluronidase
brompheniramine 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.
- hydralazine
hydralazine, phenylephrine. Mechanism: pharmacodynamic antagonism. Use Caution/Monitor. Sympathomimetics can antagonize the activity of some antihypertensive agents.
- hydromorphone
brompheniramine and hydromorphone both increase sedation. Use Caution/Monitor.
hydromorphone increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - hydroxyzine
hydroxyzine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and hydroxyzine both increase sedation. Use Caution/Monitor. - iloperidone
brompheniramine and iloperidone both increase sedation. Use Caution/Monitor.
iloperidone increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - imipramine
brompheniramine and imipramine both increase sedation. Use Caution/Monitor.
imipramine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - indacaterol, inhaled
phenylephrine increases effects of indacaterol, inhaled by Other (see comment). Use Caution/Monitor. Comment: If additional adrenergic drugs are to be administered by any route, they should be used with caution because the sympathetic effects of indacaterol may be potentiated.
- isoniazid
dextromethorphan and isoniazid both increase serotonin levels. Modify Therapy/Monitor Closely.
- L-tryptophan
dextromethorphan and L-tryptophan both increase serotonin levels. Modify Therapy/Monitor Closely.
- isoproterenol
brompheniramine increases and isoproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- insulin degludec
phenylephrine decreases effects of insulin degludec by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. Sympathomimetics increase blood glucose by stimulating alpha and beta receptors; this action results in increased hepatic glucose production, glycogenolysis, and decreased insulin secretion.
- insulin degludec/insulin aspart
phenylephrine decreases effects of insulin degludec/insulin aspart by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. Sympathomimetics increase blood glucose by stimulating alpha and beta receptors; this action results in increased hepatic glucose production, glycogenolysis, and decreased insulin secretion.
- insulin inhaled
phenylephrine decreases effects of insulin inhaled by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. Sympathomimetics increase blood glucose by stimulating alpha and beta receptors; this action results in increased hepatic glucose production, glycogenolysis, and decreased insulin secretion.
- isoproterenol
isoproterenol and phenylephrine both decrease sedation. Use Caution/Monitor.
isoproterenol and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - kava
kava increases effects of brompheniramine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.
- ketamine
ketamine and brompheniramine both increase sedation. Use Caution/Monitor.
- ketotifen, ophthalmic
ketotifen, ophthalmic increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and ketotifen, ophthalmic both increase sedation. Use Caution/Monitor. - lasmiditan
lasmiditan, brompheniramine. 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.
- letermovir
letermovir increases levels of dextromethorphan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- levalbuterol
levalbuterol and phenylephrine both decrease sedation. Use Caution/Monitor.
levalbuterol and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - lemborexant
lemborexant, brompheniramine. 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.
- levalbuterol
brompheniramine increases and levalbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- levorphanol
levorphanol increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and levorphanol both increase sedation. Use Caution/Monitor. - lisdexamfetamine
brompheniramine increases and lisdexamfetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
lisdexamfetamine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
lisdexamfetamine and phenylephrine both decrease sedation. Use Caution/Monitor. - lithium
dextromethorphan and lithium both increase serotonin levels. Modify Therapy/Monitor Closely.
- lofepramine
brompheniramine and lofepramine both increase sedation. Use Caution/Monitor.
lofepramine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - lofexidine
brompheniramine and lofexidine both increase sedation. Use Caution/Monitor.
lofexidine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - loprazolam
loprazolam increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and loprazolam both increase sedation. Use Caution/Monitor. - lorazepam
brompheniramine and lorazepam both increase sedation. Use Caution/Monitor.
lorazepam increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - lormetazepam
brompheniramine and lormetazepam both increase sedation. Use Caution/Monitor.
lormetazepam increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - loxapine
dextromethorphan, loxapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
loxapine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and loxapine both increase sedation. Use Caution/Monitor. - loxapine inhaled
loxapine inhaled increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
dextromethorphan, loxapine inhaled. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
brompheniramine and loxapine inhaled both increase sedation. Use Caution/Monitor. - lsd
dextromethorphan and lsd both increase serotonin levels. Modify Therapy/Monitor Closely.
- lurasidone
lurasidone, brompheniramine. 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.
- lumefantrine
lumefantrine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.
- lurasidone
dextromethorphan, lurasidone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- maprotiline
maprotiline increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- maprotiline
brompheniramine and maprotiline both increase sedation. Use Caution/Monitor.
- marijuana
brompheniramine and marijuana both increase sedation. Use Caution/Monitor.
marijuana increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - melatonin
brompheniramine and melatonin both increase sedation. Use Caution/Monitor.
melatonin increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - meperidine
brompheniramine and meperidine both increase sedation. Use Caution/Monitor.
meperidine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - meprobamate
meprobamate increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and meprobamate both increase sedation. Use Caution/Monitor. - metaproterenol
brompheniramine increases and metaproterenol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
metaproterenol and phenylephrine both decrease sedation. Use Caution/Monitor.
metaproterenol and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - metaxalone
brompheniramine and metaxalone both increase sedation. Use Caution/Monitor.
- methadone
methadone increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- methadone
brompheniramine and methadone both increase sedation. Use Caution/Monitor.
- methamphetamine
methamphetamine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
methamphetamine and phenylephrine both decrease sedation. Use Caution/Monitor.
brompheniramine increases and methamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - methocarbamol
brompheniramine and methocarbamol both increase sedation. Use Caution/Monitor.
- methyldopa
methyldopa increases effects of phenylephrine by unknown mechanism. Use Caution/Monitor.
- methylenedioxymethamphetamine
methylenedioxymethamphetamine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
methylenedioxymethamphetamine and phenylephrine both decrease sedation. Use Caution/Monitor.
brompheniramine increases and methylenedioxymethamphetamine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - midazolam
brompheniramine and midazolam both increase sedation. Use Caution/Monitor.
midazolam increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - midazolam intranasal
midazolam intranasal, brompheniramine. Either increases effects of the other by pharmacodynamic synergism. Modify Therapy/Monitor Closely. Concomitant use of barbiturates, alcohol, or other CNS depressants may increase the risk of hypoventilation, airway obstruction, desaturation, or apnea and may contribute to profound and/or prolonged drug effect.
- midodrine
midodrine and phenylephrine both decrease sedation. Use Caution/Monitor.
midodrine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - midodrine
brompheniramine increases and midodrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- mirtazapine
dextromethorphan and mirtazapine both increase serotonin levels. Modify Therapy/Monitor Closely.
mirtazapine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and mirtazapine both increase sedation. Use Caution/Monitor. - modafinil
brompheniramine increases and modafinil decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
modafinil and phenylephrine both decrease sedation. Use Caution/Monitor. - molindone
dextromethorphan, molindone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- morphine
dextromethorphan and morphine both increase serotonin levels. Modify Therapy/Monitor Closely.
brompheniramine and morphine both increase sedation. Use Caution/Monitor.
morphine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - motherwort
brompheniramine and motherwort both increase sedation. Use Caution/Monitor.
motherwort increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - naratriptan
naratriptan and dextromethorphan both increase serotonin levels. Modify Therapy/Monitor Closely.
- moxonidine
moxonidine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and moxonidine both increase sedation. Use Caution/Monitor. - nabilone
brompheniramine and nabilone both increase sedation. Use Caution/Monitor.
nabilone increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - nadolol
nadolol increases effects of phenylephrine by pharmacodynamic synergism. Use Caution/Monitor. Risk of acute hypertensive episode (rare).
- nalbuphine
brompheniramine and nalbuphine both increase sedation. Use Caution/Monitor.
- nalbuphine
nalbuphine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- norepinephrine
norepinephrine and phenylephrine both decrease sedation. Use Caution/Monitor.
norepinephrine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
brompheniramine increases and norepinephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - nortriptyline
brompheniramine and nortriptyline both increase sedation. Use Caution/Monitor.
nortriptyline increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - olanzapine
brompheniramine and olanzapine both increase sedation. Use Caution/Monitor.
olanzapine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
dextromethorphan, olanzapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction). - olodaterol inhaled
phenylephrine and olodaterol inhaled both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. Caution with coadministration of adrenergic drugs by any route because of additive sympathetic effects
- paliperidone
dextromethorphan, paliperidone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- opium tincture
brompheniramine and opium tincture both increase sedation. Use Caution/Monitor.
- opium tincture
opium tincture increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- orphenadrine
brompheniramine and orphenadrine both increase sedation. Use Caution/Monitor.
- oxazepam
brompheniramine and oxazepam both increase sedation. Use Caution/Monitor.
oxazepam increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - oxycodone
brompheniramine and oxycodone both increase sedation. Use Caution/Monitor.
oxycodone increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - oxymetazoline topical
oxymetazoline topical and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- oxymorphone
brompheniramine and oxymorphone both increase sedation. Use Caution/Monitor.
- oxymorphone
oxymorphone increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- oxytocin
oxytocin increases effects of phenylephrine by pharmacodynamic synergism. Use Caution/Monitor.
- paliperidone
brompheniramine and paliperidone both increase sedation. Use Caution/Monitor.
paliperidone increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - panobinostat
panobinostat will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor. Panobinostat can increase the levels and effects of sensitive CYP2D6 substrates or those with a narrow therapeutic index CYP2D6.
- papaveretum
brompheniramine and papaveretum both increase sedation. Use Caution/Monitor.
papaveretum increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - papaverine
brompheniramine and papaverine both increase sedation. Use Caution/Monitor.
- pazopanib
pazopanib increases levels of dextromethorphan by decreasing metabolism. Use Caution/Monitor.
- peginterferon alfa 2b
peginterferon alfa 2b, dextromethorphan. Other (see comment). Use Caution/Monitor. Comment: When patients are administered peginterferon alpha-2b with CYP2D6 substrates, the therapeutic effect of these drugs may be altered. Peginterferon alpha-2b may increase or decrease levels of CYP2D6 substrate.
- pentazocine
dextromethorphan and pentazocine both increase serotonin levels. Modify Therapy/Monitor Closely.
pentazocine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - passion flower
passion flower increases effects of brompheniramine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.
- perphenazine
dextromethorphan, perphenazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- pentazocine
brompheniramine and pentazocine both increase sedation. Use Caution/Monitor.
- pentobarbital
brompheniramine and pentobarbital both increase sedation. Use Caution/Monitor.
pentobarbital increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - perampanel
perampanel and brompheniramine both increase sedation. Use Caution/Monitor.
- perphenazine
perphenazine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
perphenazine, phenylephrine. 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. - perphenazine
brompheniramine and perphenazine both increase sedation. Use Caution/Monitor.
- phendimetrazine
brompheniramine increases and phendimetrazine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
phendimetrazine and phenylephrine both decrease sedation. Use Caution/Monitor.
phendimetrazine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - phenelzine
phenelzine increases effects of brompheniramine 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 increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- phenobarbital
brompheniramine and phenobarbital both increase sedation. Use Caution/Monitor.
- phentermine
phentermine and phenylephrine both decrease sedation. Use Caution/Monitor.
brompheniramine increases and phentermine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
phentermine and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - phenylephrine
brompheniramine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- pholcodine
pholcodine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- phenylephrine PO
brompheniramine increases and phenylephrine PO decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. .
- pholcodine
brompheniramine and pholcodine both increase sedation. Use Caution/Monitor.
- pimavanserin
dextromethorphan, pimavanserin. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- pimozide
dextromethorphan, pimozide. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
brompheniramine and pimozide both increase sedation. Use Caution/Monitor.
pimozide increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - pindolol
pindolol increases effects of phenylephrine by pharmacodynamic synergism. Use Caution/Monitor. Risk of acute hypertensive episode (rare).
- quetiapine
dextromethorphan, quetiapine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- pirbuterol
brompheniramine increases and pirbuterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- pirbuterol
pirbuterol and phenylephrine both decrease sedation. Use Caution/Monitor.
pirbuterol and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - pregabalin
pregabalin, brompheniramine. 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 increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and primidone both increase sedation. Use Caution/Monitor. - prochlorperazine
brompheniramine and prochlorperazine both increase sedation. Use Caution/Monitor.
prochlorperazine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
prochlorperazine, phenylephrine. 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, phenylephrine. 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
brompheniramine and promethazine both increase sedation. Use Caution/Monitor.
- promethazine
promethazine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
promethazine, phenylephrine. 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. - propofol
propofol increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
propofol and brompheniramine both increase sedation. Use Caution/Monitor. - propranolol
propranolol increases effects of phenylephrine by pharmacodynamic synergism. Use Caution/Monitor. Risk of acute hypertensive episode (rare).
- propylhexedrine
brompheniramine increases and propylhexedrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- propylhexedrine
phenylephrine and propylhexedrine both decrease sedation. Use Caution/Monitor.
phenylephrine and propylhexedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - protriptyline
protriptyline increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and protriptyline both increase sedation. Use Caution/Monitor. - pseudoephedrine
phenylephrine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- quazepam
brompheniramine and quazepam both increase sedation. Use Caution/Monitor.
- quazepam
quazepam increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- quetiapine
quetiapine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and quetiapine both increase sedation. Use Caution/Monitor. - quinidine
quinidine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Use Caution/Monitor.
- ramelteon
brompheniramine and ramelteon both increase sedation. Use Caution/Monitor.
- rasagiline
rasagiline increases effects of phenylephrine by pharmacodynamic synergism. Use Caution/Monitor. Risk of acute hypertensive episode.
- risperidone
brompheniramine and risperidone both increase sedation. Use Caution/Monitor.
risperidone increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
dextromethorphan, risperidone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction). - rizatriptan
rizatriptan and dextromethorphan both increase serotonin levels. Modify Therapy/Monitor Closely.
- safinamide
phenylephrine and safinamide both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. Monitor patients for hypertension if safinamide is prescribed concomitantly with prescription or nonprescription sympathomimetics, including nasal, oral, or ophthalmic decongestants and cold remedies.
- rolapitant
rolapitant will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Modify Therapy/Monitor Closely. Monitor for adverse reactions when unable to avoid coadministration with narrow therapeutic index CYP2D6 substrates.
- SAMe
dextromethorphan and SAMe both increase serotonin levels. Modify Therapy/Monitor Closely.
- salmeterol
brompheniramine increases and salmeterol decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- salmeterol
salmeterol and phenylephrine both decrease sedation. Use Caution/Monitor.
salmeterol and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - scullcap
brompheniramine and scullcap both increase sedation. Use Caution/Monitor.
scullcap increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - secobarbital
secobarbital increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and secobarbital both increase sedation. Use Caution/Monitor. - selegiline
selegiline increases effects of phenylephrine by pharmacodynamic synergism. Use Caution/Monitor. Risk of acute hypertensive episode.
- sevoflurane
sevoflurane and brompheniramine both increase sedation. Use Caution/Monitor.
- serdexmethylphenidate/dexmethylphenidate
serdexmethylphenidate/dexmethylphenidate and phenylephrine both decrease sedation. Use Caution/Monitor.
serdexmethylphenidate/dexmethylphenidate and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - shepherd's purse
brompheniramine and shepherd's purse both increase sedation. Use Caution/Monitor.
shepherd's purse increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - solriamfetol
phenylephrine and solriamfetol both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- sufentanil
brompheniramine and sufentanil both increase sedation. Use Caution/Monitor.
- sufentanil
sufentanil increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- sumatriptan
sumatriptan and dextromethorphan both increase serotonin levels. Modify Therapy/Monitor Closely.
- sumatriptan intranasal
sumatriptan intranasal and dextromethorphan both increase serotonin levels. Modify Therapy/Monitor Closely.
- tapentadol
brompheniramine and tapentadol both increase sedation. Use Caution/Monitor.
tapentadol increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - temazepam
temazepam increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and temazepam both increase sedation. Use Caution/Monitor. - terbutaline
terbutaline and phenylephrine both decrease sedation. Use Caution/Monitor.
brompheniramine increases and terbutaline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
terbutaline and phenylephrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - thioridazine
brompheniramine and thioridazine both increase sedation. Use Caution/Monitor.
thioridazine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
thioridazine, phenylephrine. 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
dextromethorphan, thiothixene. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
thiothixene increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and thiothixene both increase sedation. Use Caution/Monitor. - timolol
timolol increases effects of phenylephrine by pharmacodynamic synergism. Use Caution/Monitor. Risk of acute hypertensive episode (rare).
- tramadol
dextromethorphan and tramadol both increase serotonin levels. Modify Therapy/Monitor Closely.
- topiramate
brompheniramine and topiramate both increase sedation. Modify Therapy/Monitor Closely.
- topiramate
topiramate increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Modify Therapy/Monitor Closely.
- tramadol
brompheniramine and tramadol both increase sedation. Use Caution/Monitor.
tramadol increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - trazodone
brompheniramine and trazodone both increase sedation. Use Caution/Monitor.
trazodone increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - triazolam
brompheniramine and triazolam both increase sedation. Use Caution/Monitor.
triazolam increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - triclofos
brompheniramine and triclofos both increase sedation. Use Caution/Monitor.
triclofos increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - trifluoperazine
dextromethorphan, trifluoperazine. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
brompheniramine and trifluoperazine both increase sedation. Use Caution/Monitor.
trifluoperazine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
trifluoperazine, phenylephrine. 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 phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and trimipramine both increase sedation. Use Caution/Monitor. - ziprasidone
dextromethorphan, ziprasidone. unspecified interaction mechanism. Use Caution/Monitor. Serotonin modulators may enhance dopamine blockade, possibly increasing the risk for neuroleptic malignant syndrome. Antipsychotics may enhance serotonergic effect of serotonin modulators, which may result in serotonin syndrome. Monitor for evidence of serotonin toxicity (eg, mental status changes, autonomic instability, and neuromuscular hyperactivity) or neuroleptic malignant syndrome (eg, hyperthermia, muscle rigidity, autonomic dysfunction).
- triprolidine
brompheniramine and triprolidine both increase sedation. Use Caution/Monitor.
triprolidine increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - valerian
valerian increases effects of brompheniramine by pharmacodynamic synergism. Use Caution/Monitor. May enhance CNS depression.
- xylometazoline
phenylephrine and xylometazoline both decrease sedation. Use Caution/Monitor.
phenylephrine and xylometazoline both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - xylometazoline
brompheniramine increases and xylometazoline decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
- yohimbine
yohimbine and phenylephrine both decrease sedation. Use Caution/Monitor.
phenylephrine and yohimbine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
brompheniramine increases and yohimbine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - ziconotide
brompheniramine and ziconotide both increase sedation. Use Caution/Monitor.
ziconotide increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor. - ziprasidone
ziprasidone increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Use Caution/Monitor.
brompheniramine and ziprasidone both increase sedation. Use Caution/Monitor. - zolmitriptan
zolmitriptan and dextromethorphan both increase serotonin levels. Modify Therapy/Monitor Closely.
- zotepine
brompheniramine and zotepine both increase sedation. Use Caution/Monitor.
Minor (36)
- alfuzosin
alfuzosin, phenylephrine. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.
- amiodarone
amiodarone will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- asenapine
asenapine, phenylephrine. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.
asenapine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown. - ashwagandha
ashwagandha increases effects of brompheniramine by pharmacodynamic synergism. Minor/Significance Unknown. May enhance CNS depression.
- celecoxib
celecoxib will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- brimonidine
brimonidine increases effects of brompheniramine by pharmacodynamic synergism. Minor/Significance Unknown. Increased CNS depression.
- chloroquine
chloroquine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- cimetidine
cimetidine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- darifenacin
darifenacin will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- desmopressin
desmopressin increases effects of phenylephrine by pharmacodynamic synergism. Minor/Significance Unknown.
- diphenhydramine
diphenhydramine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- doxazosin
doxazosin, phenylephrine. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.
- dronedarone
dronedarone will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- eucalyptus
eucalyptus increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Minor/Significance Unknown.
brompheniramine and eucalyptus both increase sedation. Minor/Significance Unknown. - haloperidol
haloperidol will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- imatinib
imatinib will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- maraviroc
maraviroc will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- marijuana
marijuana will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- moxisylyte
moxisylyte, phenylephrine. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.
- nettle
nettle increases effects of brompheniramine by pharmacodynamic synergism. Minor/Significance Unknown. (High dose nettle; theoretical interaction) May enhance CNS depression.
- nilotinib
nilotinib will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- parecoxib
parecoxib will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- perphenazine
perphenazine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- phenoxybenzamine
phenoxybenzamine, phenylephrine. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.
- phentolamine
phentolamine, phenylephrine. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.
- prazosin
prazosin, phenylephrine. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.
- propafenone
propafenone will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- quinacrine
quinacrine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- ranolazine
ranolazine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- ritonavir
ritonavir will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- sage
sage increases and phenylephrine decreases sedation. Effect of interaction is not clear, use caution. Minor/Significance Unknown.
brompheniramine and sage both increase sedation. Minor/Significance Unknown. - Siberian ginseng
Siberian ginseng increases effects of brompheniramine by pharmacodynamic synergism. Minor/Significance Unknown. May enhance CNS depression.
- sertraline
sertraline will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
- silodosin
silodosin, phenylephrine. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.
- terazosin
terazosin, phenylephrine. Either decreases effects of the other by Mechanism: pharmacodynamic antagonism. Minor/Significance Unknown.
- thioridazine
thioridazine will increase the level or effect of dextromethorphan by affecting hepatic enzyme CYP2D6 metabolism. Minor/Significance Unknown.
Adverse Effects
Frequency Not Defined
Dizziness
Drowsiness
Dry mouth, throat, and nose
Thickening of mucus in nose or throat GI disturbances
Reflex tachycardia
Excitability
Restlessness
Headache
Hypertension
Severe peripheral and visceral vasoconstriction
Warnings
Contraindications
Hypersensitivity
Newborn infants, premature infants
Nursing mothers
Severe hypertension
Severe coronary artery disease or ischemic heart disease
Use within 14 days of MAO inhibitor
Narrow-angle glaucoma
Urinary retention
Peptic ulcer
During asthma attack
Treatment of lower respiratory tract conditions, including asthma
Cautions
Do not use the medicine to make a child sleepy; misuse of this medicine may cause death in very young children
See healthcare professional if symptoms do not improve after 7 days, or experiencing fever, rash, or headaches
If surgery or medical tests need to be performed, tell doctor ahead of time if medicine taken within past few days
Avoid becoming overheated or dehydrated during exercise and hot weather; this medicine can decrease sweating and you may be more prone to heat stroke
Patients with persistent cough, such as occurs with smoking, asthma, emphysema, or where cough is accompanied by excessive secretions should not take this product; persistent cough may be sign of serious condition
If cough persists for more than 1 week, tends to recur, or is accompanied by fever, rash, or persistent headache, consult a doctor
Use caution when giving to children or patients with chronic pulmonary disease, shortness of breath, difficulty in breathing, asthma, emphysema, high blood pressure, heart disease, diabetes, thyroid disease, or difficulty in urination due to enlargement of the prostate gland unless directed by a physician
Antihistamines may impair mental and physical abilities required for performance of potentially hazardous tasks, such as driving a car or operating machinery and may impair mental alertness in children
At doses higher than recommended dose, nervousness, dizziness, or sleeplessness may occur; especially in infants and small children, antihistamines in overdosage may cause hallucinations, convulsions, and death
If nervousness, dizziness, or sleeplessness occurs, discontinue use and consult healthcare professional
Administration of dextromethorphan hydrobromide may be accompanied by histamine release and should be used with caution in atopic children
If hypertensive crisis occurs, these drugs should be discontinued immediately and therapy to lower blood pressure instituted immediately; fever should be managed by means of external cooling
Before prescribing medication to suppress or modify cough, it is important to identify underlying cause of cough, ascertain that modification of cough does not increase risk of clinical or physiologic complications, and appropriate therapy for primary disease is provided
Because of antihistamine component, medication should be used with caution in patients with history of bronchial asthma, narrow-angle glaucoma, gastrointestinal obstruction, or urinary bladder-neck obstruction
Because of its sympathomimetic component, medication should be used with caution in patients with diabetes, hypertension, heart disease, or thyroid disease
Drug interaction overview
- MAO inhibitors prolong and intensify anticholinergic effects of antihistamines; antihistamines may have additive effects with alcohol and other CNS depressants, eg, hypnotics, sedatives, tranquilizers, antianxiety agents
- Drinking alcohol with this medication can cause side effects
Pregnancy & Lactation
Pregnancy
Animal reproduction studies not conducted; also not known whether drug combination can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity; medication should be given to a pregnant woman only if clearly needed
Lactation
Because of higher risk of intolerance of antihistamines in small infants generally, and in newborns and prematures in particular, this medication is contraindicated in nursing mothers
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.Pharmacology
Mechanism of Action
Brompheniramine: Competitively blocks histamine from binding to H1 receptors; significant antimuscarinic activity and penetrates CNS, which causes pronounced tendency to induce sedation
Dextromethorphan: Cough suppressant that acts centrally on the cough center in medulla
Phenylephrine: Vasoconstrictor & decongestant that relieves symptoms resulting from irritation of upper respiratory tract tissue; shrinks swollen mucous membranes, reduces nasal congestion and tissue hyperemia
Pharmacokinetics
Brompheniramine
- Onset: 15-30 min
- Duration: 3-9 hr, may last 48 hr
- Peak Plasma Time: 2-5 hr
- Vd: 11.7 L/kg (adults); 20 L/kg (children)
- Protein binding: 39-49%
- Metabolism: Mainly liver; metabolites include propionic acid derivative conjugated with glycine
- Half-Life: 11.8 (children); 25 hr (adults)
- Excretion: Urine
Dextromethorphan
- Onset: 15-30 min
- Duration: 3-6 hr
- Metabolism: Hepatic P450 enzyme CYP2D6
- Excretion: Urine
- Half-life: 2-4 hr (extensive metabolizers); 24 hr (poor metabolizers)
- Peak plasma time: 2-3 hr
Phenylephrine
- Half-life: 2-3 hr
- Onset: 10-15 min
- Duration: 15 min
- Bioavailability: < 38%
- Excretion: Urine (80-90%)
- Peak plasma time: 0.75-2 hr
- Vd: 26-61 L
- Vdss: 340 L
Administration
Measure liquid medicine with supplied measuring device (not kitchen spoon)
This medication is to be used as needed; if scheduled doses necessary and missed a dose, skip missed dose; do not use two doses at one time
Do not administer 6 doses in 24 hr