Dosing & Uses
Dosage Forms & Strengths
guaifenesin/pseudoephedrine
caplet
- 400mg/60mg
tablet
- 400mg/20mg
- 400mg/30mg
- 400mg/40mg
- 400mg/60mg
tablet extended release
- 1200mg/120mg
- 600mg/60mg
Nasal Congestion, Loosening of Phlegm & Thin Bronchial Secretions
Musinex –D 600/60: 1-2 tab or cap PO q12hr; not to exceed 4 tab or cap/24hr
Musinex –D 1200/120: 1 tab or cap PO q12hr; not to exceed 2 tab or cap/24 hr
Congestac: 1 caplet PO q4-6hr; not to exceed 4 caplets/24hr
Maxifed G: 1-2 tap PO q12hr; not to exceed 4 tab/24hr
Maxifed: 1-1½ tab PO q12hr; not to exceed 3 tab/24hr
Dosage Forms & Strengths
guaifenesin/pseudoephedrine
caplet
- 400mg/60mg
tablet
- 400mg/20mg
- 400mg/30mg
- 400mg/40mg
- 400mg/60mg
tablet extended release
- 1200mg/120mg
- 600mg/60mg
Nasal Congestion, Loosening of Phlegm & Thin Bronchial Secretions
<6 years
- Ask a pediatrician
6-12 Years
- Ambifed G, Maxifed: ½ tab or cap PO q12hr; not to exceed 1 tab or cap/24hr
- Congestac: ½ caplet PO q4-6hr; not to exceed 2 caplets/24hr
- Maxifed-G: ½ - 1 tab PO q12hr; not to exceed 2 tab/24hr
>12 Years
- Musinex –D 600/60: 1-2 tab or cap PO q12hr; not to exceed 4 tab or cap/24hr
- Musinex –D 1200/120: 1 tab or cap PO q12hr; not to exceed 2 tab or cap/24 hr
- Congestac: 1 caplet PO q4-6hr; not to exceed 4 caplets/24hr
- Maxifed G: 1-2 tap PO q12hr; not to exceed 4 tab/24hr
- Maxifed: 1-1½ tab PO q12hr; not to exceed 3 tab/24hr
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Contraindicated (15)
- dihydroergotamine
dihydroergotamine increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Ergot derivatives may enhance the vasoconstricting effect of pseudoephedrine and eventually significantly increasing blood pressure.
- dihydroergotamine inhaled
dihydroergotamine inhaled increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Ergot derivatives may enhance the vasoconstricting effect of pseudoephedrine and eventually significantly increasing blood pressure.
- dihydroergotamine intranasal
dihydroergotamine intranasal increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Ergot derivatives may enhance the vasoconstricting effect of pseudoephedrine and eventually significantly increasing blood pressure.
- ergoloid mesylates
ergoloid mesylates increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Ergot derivatives may enhance the vasoconstricting effect of pseudoephedrine and eventually significantly increasing blood pressure.
- ergonovine
ergonovine increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Ergot derivatives may enhance the vasoconstricting effect of pseudoephedrine and eventually significantly increasing blood pressure.
- ergotamine
ergotamine increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Ergot derivatives may enhance the vasoconstricting effect of pseudoephedrine and eventually significantly increasing blood pressure.
- isocarboxazid
isocarboxazid increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- linezolid
linezolid increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- methylergonovine
methylergonovine increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Ergot derivatives may enhance the vasoconstricting effect of pseudoephedrine and eventually significantly increasing blood pressure.
- phenelzine
phenelzine increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- procarbazine
procarbazine increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- rasagiline
rasagiline increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- selegiline
selegiline increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- selegiline transdermal
selegiline transdermal increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
- tranylcypromine
tranylcypromine increases effects of pseudoephedrine by pharmacodynamic synergism. Contraindicated. Risk of acute hypertensive episode.
Serious - Use Alternative (26)
- amitriptyline
amitriptyline increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. 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 increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.
- cabergoline
cabergoline, pseudoephedrine. Mechanism: pharmacodynamic synergism. Contraindicated. Additive vasospasm; risk of hypertension.
- clomipramine
clomipramine increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.
- cocaine topical
cocaine topical increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug.
- desipramine
desipramine increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.
- desvenlafaxine
desvenlafaxine increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug.
- doxapram
doxapram increases effects of pseudoephedrine by pharmacodynamic synergism. Avoid or Use Alternate Drug. Additive pressor effect.
- doxepin
doxepin increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. 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 increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug.
- imipramine
imipramine increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.
- iobenguane I 123
pseudoephedrine decreases effects of iobenguane I 123 by receptor binding competition. Avoid or Use Alternate Drug. If clinically appropriate, discontinue drugs that compete for NE receptor sites for at least 5 half-lives; may cause false-negative imaging results. Do not administer pseudoephedrine until at least 7 days after each iobenguane dose.
- iobenguane I 131
pseudoephedrine decreases effects of iobenguane I 131 by receptor binding competition. Avoid or Use Alternate Drug. If clinically appropriate, discontinue drugs that compete for NE receptor sites for at least 5 half-lives; may cause false-negative imaging results. Do not administer pseudoephedrine until at least 7 days after each iobenguane dose.
- isoflurane
isoflurane increases toxicity of pseudoephedrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.
- levomilnacipran
levomilnacipran increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug.
- lofepramine
lofepramine, pseudoephedrine. 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, pseudoephedrine. Other (see comment). Avoid or Use Alternate Drug. Comment: Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.
- methoxyflurane
methoxyflurane increases toxicity of pseudoephedrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.
- milnacipran
milnacipran increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug.
- nortriptyline
nortriptyline increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.
- ozanimod
ozanimod increases toxicity of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Because the active metabolite of ozanimod inhibits MAO-B in vitro, there is a potential for serious adverse reactions, including hypertensive crisis. Therefore, coadministration of ozanimod with drugs that can increase norepinephrine or serotonin is not recommended. Monitor for hypertension with concomitant use.
- protriptyline
protriptyline increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.
- sevoflurane
sevoflurane increases toxicity of pseudoephedrine by Mechanism: unknown. Avoid or Use Alternate Drug. Risk of V tach, HTN.
- trazodone
trazodone, pseudoephedrine. 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 increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug. Tricyclic antidepressants increase or decrease effects of sympathomimetics, by blocking reuptake of NE, or blocking uptake of indirect sympathomimetics into the adrenergic neuron.
- venlafaxine
venlafaxine increases effects of pseudoephedrine by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Avoid or Use Alternate Drug.
Monitor Closely (73)
- acetazolamide
acetazolamide will increase the level or effect of pseudoephedrine by passive renal tubular reabsorption - basic urine. Use Caution/Monitor.
- albuterol
albuterol and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- alfuzosin
pseudoephedrine decreases effects of alfuzosin by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- aluminum hydroxide
aluminum hydroxide will increase the level or effect of pseudoephedrine by passive renal tubular reabsorption - basic urine. Use Caution/Monitor. Caution advised with frequent or high dose antacids
- ammonium chloride
ammonium chloride decreases effects of pseudoephedrine by unknown mechanism. Use Caution/Monitor. Urinary excretion of indirect acting alpha/beta agonists (eg, pseudoephedrine) may increase when administered concomitantly with urinary acidifying agents, resulting in lower serum concentrations.
- arformoterol
arformoterol and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- benzphetamine
benzphetamine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- bromocriptine
bromocriptine, pseudoephedrine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Hypertension, V tach.
- chlorpromazine
chlorpromazine, pseudoephedrine. Mechanism: unknown. Use Caution/Monitor. Consider avoiding use of pseudoephedrine in patients receiving phenothiazines (especially thioridazine) due to the potential risk of cardiac arrhythmia or sudden death. Monitor for evidence of ventricular arrhythmias during concomitant use.
- dexfenfluramine
dexfenfluramine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- dexmethylphenidate
dexmethylphenidate and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- dextroamphetamine
dextroamphetamine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- diethylpropion
diethylpropion and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- dobutamine
dobutamine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- dopamine
dopamine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- dopexamine
dopexamine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- doxazosin
pseudoephedrine decreases effects of doxazosin by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- droxidopa
pseudoephedrine and droxidopa both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. May increase risk for supine hypertension
- ephedrine
ephedrine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
ephedrine, pseudoephedrine. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. - epinephrine
epinephrine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- epinephrine inhaled
pseudoephedrine, epinephrine inhaled. Either increases effects of the other by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- epinephrine racemic
epinephrine racemic and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- esketamine intranasal
esketamine intranasal, pseudoephedrine. Either increases toxicity of the other by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. Closely monitor blood pressure with concomitant use of esketamine nasal with stimulants. .
- fenfluramine
fenfluramine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- fluphenazine
fluphenazine, pseudoephedrine. Mechanism: unknown. Use Caution/Monitor. Consider avoiding use of pseudoephedrine in patients receiving phenothiazines (especially thioridazine) due to the potential risk of cardiac arrhythmia or sudden death. Monitor for evidence of ventricular arrhythmias during concomitant use.
- formoterol
formoterol and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- hydralazine
hydralazine, pseudoephedrine. Mechanism: pharmacodynamic antagonism. Use Caution/Monitor. Sympathomimetics can antagonize the activity of some antihypertensive agents.
- insulin degludec
pseudoephedrine 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
pseudoephedrine 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 detemir
pseudoephedrine decreases effects of insulin detemir 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 glargine
pseudoephedrine decreases effects of insulin glargine 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
pseudoephedrine 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.
- insulin regular human
pseudoephedrine decreases effects of insulin regular human 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 pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- levalbuterol
levalbuterol and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- lisdexamfetamine
lisdexamfetamine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- metaproterenol
metaproterenol and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- methamphetamine
methamphetamine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- methenamine
methenamine decreases effects of pseudoephedrine by unknown mechanism. Use Caution/Monitor. Urinary excretion of indirect acting alpha/beta agonists (eg, pseudoephedrine) may increase when administered concomitantly with urinary acidifying agents, resulting in lower serum concentrations.
- methyldopa
methyldopa increases effects of pseudoephedrine by unknown mechanism. Use Caution/Monitor.
- methylenedioxymethamphetamine
methylenedioxymethamphetamine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- midodrine
midodrine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- nateglinide
pseudoephedrine decreases effects of nateglinide by pharmacodynamic antagonism. Use Caution/Monitor. Coadministration may reduce nateglinide's hypoglycemic action.
- norepinephrine
norepinephrine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- olodaterol inhaled
pseudoephedrine 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
- oxytocin
oxytocin increases effects of pseudoephedrine by pharmacodynamic synergism. Use Caution/Monitor.
- perphenazine
perphenazine, pseudoephedrine. Mechanism: unknown. Use Caution/Monitor. Consider avoiding use of pseudoephedrine in patients receiving phenothiazines (especially thioridazine) due to the potential risk of cardiac arrhythmia or sudden death. Monitor for evidence of ventricular arrhythmias during concomitant use.
- phendimetrazine
phendimetrazine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- phentermine
phentermine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- phenylephrine
phenylephrine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- phenylephrine PO
phenylephrine PO and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- pirbuterol
pirbuterol and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- potassium phosphate
potassium phosphate decreases effects of pseudoephedrine by unknown mechanism. Use Caution/Monitor. Urinary excretion of indirect acting alpha/beta agonists (eg, pseudoephedrine) may increase when administered concomitantly with urinary acidifying agents, resulting in lower serum concentrations.
- prochlorperazine
prochlorperazine, pseudoephedrine. Mechanism: unknown. Use Caution/Monitor. Consider avoiding use of pseudoephedrine in patients receiving phenothiazines (especially thioridazine) due to the potential risk of cardiac arrhythmia or sudden death. Monitor for evidence of ventricular arrhythmias during concomitant use.
- promazine
promazine, pseudoephedrine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only.
- promethazine
promethazine, pseudoephedrine. Mechanism: unknown. Use Caution/Monitor. Risk of cardiac arrhythmia or sudden death, more likely w/thioridazine than other phenothiazines. Interaction more likely in certain predisposed pts. only.
- propylhexedrine
propylhexedrine and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- safinamide
pseudoephedrine 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.
- salmeterol
salmeterol and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- serdexmethylphenidate/dexmethylphenidate
serdexmethylphenidate/dexmethylphenidate and pseudoephedrine both decrease sedation. Use Caution/Monitor.
serdexmethylphenidate/dexmethylphenidate and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor. - silodosin
pseudoephedrine decreases effects of silodosin by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- sodium bicarbonate
sodium bicarbonate will increase the level or effect of pseudoephedrine by passive renal tubular reabsorption - basic urine. Use Caution/Monitor. Caution advised with frequent or high dose antacids
- sodium citrate/citric acid
sodium citrate/citric acid will increase the level or effect of pseudoephedrine by passive renal tubular reabsorption - basic urine. Use Caution/Monitor.
- sodium lactate
sodium lactate will increase the level or effect of pseudoephedrine by passive renal tubular reabsorption - basic urine. Use Caution/Monitor.
- sodium phosphates, IV
sodium phosphates, IV decreases effects of pseudoephedrine by unknown mechanism. Use Caution/Monitor. Urinary excretion of indirect acting alpha/beta agonists (eg, pseudoephedrine) may increase when administered concomitantly with urinary acidifying agents, resulting in lower serum concentrations.
- solriamfetol
pseudoephedrine and solriamfetol both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- spironolactone
spironolactone decreases effects of pseudoephedrine by pharmacodynamic antagonism. Use Caution/Monitor.
- tamsulosin
pseudoephedrine decreases effects of tamsulosin by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- terazosin
pseudoephedrine decreases effects of terazosin by sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- terbutaline
terbutaline and pseudoephedrine both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
- thioridazine
thioridazine, pseudoephedrine. Mechanism: unknown. Use Caution/Monitor. Consider avoiding use of pseudoephedrine in patients receiving phenothiazines (especially thioridazine) due to the potential risk of cardiac arrhythmia or sudden death. Monitor for evidence of ventricular arrhythmias during concomitant use.
- trifluoperazine
trifluoperazine, pseudoephedrine. Mechanism: unknown. Use Caution/Monitor. Consider avoiding use of pseudoephedrine in patients receiving phenothiazines (especially thioridazine) due to the potential risk of cardiac arrhythmia or sudden death. Monitor for evidence of ventricular arrhythmias during concomitant use.
- xylometazoline
pseudoephedrine and xylometazoline both increase sympathetic (adrenergic) effects, including increased blood pressure and heart rate. Use Caution/Monitor.
Minor (1)
- desmopressin
desmopressin increases effects of pseudoephedrine by pharmacodynamic synergism. Minor/Significance Unknown.
Adverse Effects
Frequency Not Defined
Arrhythmia
Palpitations
Convulsion
Dizziness
Drowsiness
Excitability
Headache
Tremor
Weakness
Nausea
Vomiting
Warnings
Contraindications
Contraindicated in documented hypersensitivity to either drug or components
Within 14 days of MAO inhibitor therapy
Cautions
Use caution in high blood pressure, thyroid disease
Caution in cardiovascular disease, diabetes mellitus, prostatic hypertrophy, and increased intraocular pressure when taking pseudoephedrine
Guaifenesin is not for administration in persistent cough associated with chronic bronchitis, smoking, asthma, or accompanied by excessive secretions
Discontinue use if you experience dizziness, insomnia, nervousness, experience persistent headache, symptoms do not improve within 7 days, or occur with a fever
Pregnancy & Lactation
Pregnant or breastfeeding patients should seek advice of health professional before using OTC drugs
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Mechanism of Action
Guaifenesin increases respiratory tract fluid secretions and helps to loosen phlegm and bronchial secretions
Pseudoephedrine stimulates the alpha-adrenergic receptors causing bronchodilation and vasoconstriction
Pharmacokinetics
Guaifenesin
- Half-Life: 1 hr
- Onset: 30 min
- Duration: 4-6 hr
- Metabolism: Liver
- Metabolite: b-(2-methoxyphenoxy) lactic acid
- Excretion: Urine
Pseudoephedrine
- Half-Life: 3 hr (children); 9-16 hr (adults)
- Onset: 30 min (decongestant)
- Duration: 3-8 hr
- Peak Plasma Time: 1.97 hr
- Concentration: 422 ng/mL
- Metabolism: Liver, by N-demethylation
- Metabolites: Inactive
- Clearance: 7.3-7.6 mL/min/kg
- Excretion: Urine (43-96%)