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]
Syrup, Oral:
TGQ 30PSE/150GFN/15DM: Guaifenesin 150 mg, pseudoephedrine hydrochloride 30 mg, and dextromethorphan hydrobromide 15 mg per 5 mL (473 mL [DSC]) [contains methylparaben, propylene glycol, propylparaben]
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)]
Pharmacology
Mechanism of Action
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.
Dosage and Administration
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
Dosing: Geriatric
Refer to adult dosing.
Dosing: Pediatric
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):
Children 6 to 11 years: One-half tablet every 4 hours, up to 2 tablets per day
Children ≥12 years of age and Adolescents: One tablet every 4 hours, up to 4 tablets per day
Tablets (dextromethorphan 15 mg/guaifenesin 400 mg/pseudoephedrine 60 mg):
Children 6 to 11 years: One-half tablet every 4 hours, up to 2 tablets per day
Children ≥12 years of age and Adolescents: One tablet every 4 hours, up to 4 tablets per day
Administration
Administer without regard to food.
Storage
Store at room temperature.
Drug Interactions
Abiraterone Acetate: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Management: Avoid concurrent use of abiraterone with CYP2D6 substrates that have a narrow therapeutic index whenever possible. When concurrent use is not avoidable, monitor patients closely for signs/symptoms of toxicity. Consider therapy modification
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
Asunaprevir: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Consider therapy modification
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
CloBAZam: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). 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 decrease the metabolism of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy
CYP2D6 Inhibitors (Strong): May decrease the metabolism of CYP2D6 Substrates (High risk with Inhibitors). Consider therapy modification
Dacomitinib: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Management: Avoid concurrent use of dacomitinib with CYP2D6 subtrates that have a narrow therapeutic index. Consider therapy modification
Darunavir: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy
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
Imatinib: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). 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
Monoamine Oxidase Inhibitors: May enhance the serotonergic effect of Dextromethorphan. This may cause serotonin syndrome. Avoid combination
Panobinostat: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy
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
Perhexiline: CYP2D6 Substrates (High risk with Inhibitors) may increase the serum concentration of Perhexiline. Perhexiline may increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). Monitor therapy
QuiNIDine: May increase the serum concentration of Dextromethorphan. Management: Avoid concurrent use of these agents when possible, unless the increased psychoactive effects of dextromethorphan are desired. Since codeine activation is also inhibited by quinidine, codeine is unlikely to be suitable as an alternative antitussive. Consider therapy modification
QuiNINE: May increase the serum concentration of CYP2D6 Substrates (High risk with Inhibitors). 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. Consider therapy modification
Solriamfetol: Sympathomimetics may enhance the hypertensive 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
Tipranavir: May increase the serum concentration of Dextromethorphan. Management: Consider avoiding dextromethorphan in patients taking tipranavir. If combined, monitor closely for increased dextromethorphan effects/toxicities. Consider therapy modification
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.
Concurrent drug therapy issues:
- Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.
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
Pregnancy Considerations
See individual agents.
Patient Education
- Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
- Patient may experience dizziness, anxiety, or trouble sleeping (HCAHPS).
- Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.
Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.
