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Guaifenesin, Pseudoephedrine, and Dextromethorphan

Medically reviewed by Drugs.com. Last updated on Jul 16, 2020.

Pronunciation

(gwye FEN e sin, soo doe e FED rin, & deks troe meth OR fan)

Index Terms

  • Dextromethorphan, Guaifenesin, and Pseudoephedrine
  • Pseudoephedrine, Dextromethorphan, and Guaifenesin

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Liquid, Oral:

Entre-Cough: Guaifenesin 175 mg, pseudoephedrine hydrochloride 30 mg, and dextromethorphan hydrobromide 15 mg per 5 mL (473 mL [DSC]) [contains aspartame, fd&c red #40, methylparaben, sodium benzoate; cherry flavor]

Tablet, Oral:

Capmist DM: Guaifenesin 400 mg, pseudoephedrine hydrochloride 60 mg, and dextromethorphan hydrobromide 15 mg [scored; contains brilliant blue fcf (fd&c blue #1), tartrazine (fd&c yellow #5)]

Poly-Vent DM: Guaifenesin 380 mg, pseudoephedrine hydrochloride 60 mg, and dextromethorphan hydrobromide 20 mg [scored; contains tartrazine (fd&c yellow #5)]

Brand Names: U.S.

  • Capmist DM [OTC]
  • Entre-Cough [OTC] [DSC]
  • Poly-Vent DM [OTC]

Pharmacologic Category

  • Antitussive/Decongestant/Expectorant

Pharmacology

See individual agents.

Use: Labeled Indications

Cough and upper respiratory tract symptoms: Temporarily relieves nasal congestion, sneezing, nasal/throat irritation, itchy/watery eyes, and controls cough due to minor throat and bronchial irritation associated with the common cold, hay fever, or other upper respiratory allergies; helps loosen phlegm (mucus) and thin bronchial secretions to make coughs more productive; reduces swelling of nasal passages.

Contraindications

Concurrent administration with or within 2 weeks of discontinuing a monoamine oxidase inhibitor.

Dosing: Adult

Cough and upper respiratory tract symptoms: Oral: Note: Dosing may vary by product. Consult specific product labeling.

Tablets (dextromethorphan 20 mg/guaifenesin 380 mg/pseudoephedrine 60 mg): One tablet every 4 hours, up to 4 tablets per day

Tablets (dextromethorphan 15 mg/guaifenesin 400 mg/pseudoephedrine 60 mg): One tablet every 4 hours, up to 4 tablets per day

Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Note: Multiple concentrations of oral liquid formulations (liquid, solution, and syrup) and strengths of oral tablets exist; close attention must be paid to the concentration when ordering or administering. Refer to product-specific labeling for approved pediatric ages. Safety and efficacy for the use of cough and cold products in infants and young children is limited; the AAP warns against the use of these products for respiratory illnesses in infants and young children; the FDA does not recommend OTC use in infants and children <2 years of age due to the risk of serious and life-threatening adverse effects (including death) and recommends to use with caution in pediatric patients ≥2 years of age (AAP 2018; FDA 2017).

Cough and upper respiratory tract symptoms: Note: Approved ages and uses for generic products may vary; consult labeling for specific information.

Liquid:

Dextromethorphan 10 mg/guaifenesin 187 mg/pseudoephedrine 30 mg per 5 mL (eg, Pecgen PSE, Trispec PSE):

Children 2 to <6 years: Oral: 2.5 mL every 4 hours as needed; maximum dose: 10 mL/24 hours.

Children ≥6 to <12 years: Oral: 5 mL every 4 hours as needed; maximum dose: 20 mL/24 hours.

Children ≥12 years and Adolescents: Oral: 10 mL every 4 hours as needed; maximum dose: 40 mL/24 hours.

Tablets:

Dextromethorphan 20 mg/guaifenesin 380 mg/pseudoephedrine 60 mg per tablet (eg, Polyvent DM):

Children 6 to <12 years: Oral: 1/2 tablet every 4 hours as needed; maximum dose: 2 tablets/24 hours.

Children ≥12 years and Adolescents: Oral: One tablet every 4 hours as needed; maximum dose: 4 tablets/24 hours.

Dextromethorphan 15 mg/guaifenesin 400 mg/pseudoephedrine 60 mg per tablet (eg, Capmist DM):

Children 6 to <12 years: Oral: 1/2 tablet every 4 hours as needed; maximum dose: 2 tablets/24 hours.

Children ≥12 years and Adolescents: Oral: One tablet every 4 hours as needed; maximum dose: 4 tablets/24 hours.

Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.

Administration

Administer without regard to food.

Storage

Store at room temperature.

Drug Interactions

Ajmaline: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

Alkalinizing Agents: May increase the serum concentration of Alpha-/Beta-Agonists (Indirect-Acting). Monitor therapy

Alpha1-Blockers: May diminish the vasoconstricting effect of Alpha-/Beta-Agonists. Similarly, Alpha-/Beta-Agonists may antagonize Alpha1-Blocker vasodilation. Monitor therapy

AtoMOXetine: May enhance the hypertensive effect of Sympathomimetics. AtoMOXetine may enhance the tachycardic effect of Sympathomimetics. Monitor therapy

Benzylpenicilloyl Polylysine: Alpha-/Beta-Agonists may diminish the diagnostic effect of Benzylpenicilloyl Polylysine. Management: Consider use of a histamine skin test as a positive control to assess a patient's ability to mount a wheal and flare response. Consider therapy modification

Cannabinoid-Containing Products: May enhance the tachycardic effect of Sympathomimetics. Exceptions: Cannabidiol. Monitor therapy

Carbonic Anhydrase Inhibitors: May increase the serum concentration of Alpha-/Beta-Agonists (Indirect-Acting). Monitor therapy

Chloroprocaine: May enhance the hypertensive effect of Alpha-/Beta-Agonists. Monitor therapy

Cobicistat: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

Cocaine (Topical): May enhance the hypertensive effect of Sympathomimetics. Management: Consider alternatives to use of this combination when possible. Monitor closely for substantially increased blood pressure or heart rate and for any evidence of myocardial ischemia with concurrent use. Consider therapy modification

CYP2D6 Inhibitors (Moderate): May increase the serum concentration of Dextromethorphan. Exceptions: DULoxetine. Monitor therapy

CYP2D6 Inhibitors (Strong): May increase the serum concentration of Dextromethorphan. Monitor therapy

Disulfiram: May enhance the adverse/toxic effect of Products Containing Ethanol. Management: Do not use disulfiram with dosage forms that contain ethanol. Avoid combination

Doxofylline: Sympathomimetics may enhance the adverse/toxic effect of Doxofylline. Monitor therapy

Ergot Derivatives: May enhance the hypertensive effect of Alpha-/Beta-Agonists. Ergot Derivatives may enhance the vasoconstricting effect of Alpha-/Beta-Agonists. Exceptions: Ergoloid Mesylates; Nicergoline. Avoid combination

FentaNYL: Alpha-/Beta-Agonists (Indirect-Acting) may decrease the serum concentration of FentaNYL. Specifically, fentanyl nasal spray serum concentrations may decrease and onset of effect may be delayed. Monitor therapy

Guanethidine: May enhance the arrhythmogenic effect of Sympathomimetics. Guanethidine may enhance the hypertensive effect of Sympathomimetics. Monitor therapy

Iobenguane Radiopharmaceutical Products: Alpha-/Beta-Agonists (Indirect-Acting) may diminish the therapeutic effect of Iobenguane Radiopharmaceutical Products. Management: Discontinue all drugs that may inhibit or interfere with catecholamine transport or uptake for at least 5 biological half-lives before iobenguane administration. Do not administer these drugs until at least 7 days after each iobenguane dose. Avoid combination

Lumefantrine: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

Memantine: NMDA Receptor Antagonists may enhance the adverse/toxic effect of Memantine. Monitor therapy

Methotrimeprazine: Products Containing Ethanol may enhance the adverse/toxic effect of Methotrimeprazine. Specifically, CNS depressant effects may be increased. Management: Avoid products containing alcohol in patients treated with methotrimeprazine. Avoid combination

Monoamine Oxidase Inhibitors: May enhance the serotonergic effect of Dextromethorphan. This may cause serotonin syndrome. Avoid combination

Ozanimod: May enhance the hypertensive effect of Sympathomimetics. Management: Concomitant use of ozanimod with sympathomimetic agents is not recommended. If combined, monitor patients closely for the development of hypertension, including hypertensive crises. Consider therapy modification

Parecoxib: May increase the serum concentration of Dextromethorphan. Monitor therapy

Peginterferon Alfa-2b: May decrease the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Peginterferon Alfa-2b may increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy

Procarbazine: May enhance the adverse/toxic effect of Sympathomimetics. Management: Consider alternatives to this combination when possible. Procarbazine prescribing information states that this combination should be avoided. Consider therapy modification

Reserpine: May diminish the therapeutic effect of Alpha-/Beta-Agonists (Indirect-Acting). Monitor therapy

Selective Serotonin Reuptake Inhibitors (Strong CYP2D6 Inhibitors): Dextromethorphan may enhance the serotonergic effect of Selective Serotonin Reuptake Inhibitors (Strong CYP2D6 Inhibitors). This could result in serotonin syndrome. Selective Serotonin Reuptake Inhibitors (Strong CYP2D6 Inhibitors) may increase the serum concentration of Dextromethorphan. Management: Consider alternatives to this drug combination. If combined, monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes). Consider therapy modification

Serotonergic Agents (High Risk): Dextromethorphan may enhance the serotonergic effect of Serotonergic Agents (High Risk). This could result in serotonin syndrome. Management: Monitor for signs and symptoms of serotonin syndrome/serotonin toxicity (eg, hyperreflexia, clonus, hyperthermia, diaphoresis, tremor, autonomic instability, mental status changes) when these agents are combined. Exceptions: FLUoxetine; Isocarboxazid; Linezolid; Methylene Blue; Moclobemide; PARoxetine; Phenelzine; Tranylcypromine. Monitor therapy

Serotonin/Norepinephrine Reuptake Inhibitors: May enhance the tachycardic effect of Alpha-/Beta-Agonists. Serotonin/Norepinephrine Reuptake Inhibitors may enhance the vasopressor effect of Alpha-/Beta-Agonists. Management: If possible, avoid coadministration of direct-acting alpha-/beta-agonists and serotonin/norepinephrine reuptake inhibitors. If coadministered, monitor for increased sympathomimetic effects (eg, increased blood pressure, chest pain, headache). Consider therapy modification

Solriamfetol: Sympathomimetics may enhance the hypertensive effect of Solriamfetol. Sympathomimetics may enhance the tachycardic effect of Solriamfetol. Monitor therapy

Spironolactone: May diminish the vasoconstricting effect of Alpha-/Beta-Agonists. Monitor therapy

Sympathomimetics: May enhance the adverse/toxic effect of other Sympathomimetics. Monitor therapy

Tedizolid: May enhance the hypertensive effect of Sympathomimetics. Tedizolid may enhance the tachycardic effect of Sympathomimetics. Monitor therapy

Tricyclic Antidepressants: May enhance the vasopressor effect of Alpha-/Beta-Agonists. Management: Avoid, if possible, the use of alpha-/beta-agonists in patients receiving tricyclic antidepressants. If combined, monitor for evidence of increased pressor effects and consider reductions in initial dosages of the alpha-/beta-agonist. Consider therapy modification

Urinary Acidifying Agents: May decrease the serum concentration of Alpha-/Beta-Agonists (Indirect-Acting). Monitor therapy

Test Interactions

See individual agents.

Adverse Reactions

See individual agents.

Warnings/Precautions

Disease-related concerns:

• Cardiovascular disease: Use with caution in patients with cardiovascular disease (including hypertension and ischemic heart disease).

• Diabetes: Use with caution in patients with diabetes mellitus.

• Increased intraocular pressure/glaucoma: Use with caution in patients with increased intraocular pressure or glaucoma.

• Prostatic hyperplasia/urinary obstruction: Use with caution in patients with prostatic hyperplasia and/or GU obstruction.

• Respiratory disease: Use with caution in patients with a breathing problem or chronic cough that occurs with smoking, asthma, emphysema, or chronic bronchitis or a cough accompanied with too much mucus.

• Thyroid dysfunction: Use with caution in patients with thyroid dysfunction.

Special populations:

• CYP2D6 poor metabolizers: Dextromethorphan is metabolized by hepatic CYP2D6. Poor metabolizers of CYP2D6 may have exaggerated or prolonged effects of dextromethorphan. Increased risk may be seen with concomitant use of potent CYP2D6 inhibitors; use with caution (Abduljalil 2010; Jurica 2012; Sager 2014; Zhou 2009).

• Elderly: Use with caution in the elderly; may be more sensitive to adverse effects.

Other warnings/precautions:

• Cough: Appropriate use: Underlying cause of cough should be determined prior to prescribing.

• Self-medication (OTC use): Do not exceed recommended dose.

Pregnancy Considerations

Refer to individual monographs.

Patient Education

What is this drug used for?

• It is used to treat nose stuffiness.

• It is used to thin mucus so it can be taken from the body by coughing.

• It is used to relieve coughing.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Dizziness

• Anxiety

• Trouble sleeping

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.