Generic & Brand Names
Generic: Dextromethorphan Hydrobromide
Common Brands: Benylin DM®, Robitussin DM®, Corex-DX®, TusQ-DX®
Drug Class
Antitussive NMDA Receptor Antagonist Mechanism of Action
Dextromethorphan suppresses the cough reflex by acting centrally on the medullary cough center. It is a non-opioid derivative of morphine and lacks analgesic or addictive properties at therapeutic doses.
Indications
- Dry, non-productive cough
- Cough associated with upper respiratory tract infections
- Nocturnal cough
Dosage (General)
- Adults: 10–20 mg every 4 hours or 30 mg every 6–8 hours
- Children 6–12 years: 5–10 mg every 4 hours
- Children <6 years: Use only if prescribed
Maximum daily dose should not be exceeded.
Side Effects
- Drowsiness
- Dizziness
- Nausea
- Gastrointestinal discomfort
- Rarely: confusion at high doses
Contraindications & Precautions
- Hypersensitivity to dextromethorphan
- Concomitant use with MAO inhibitors
- Use with caution in asthma or chronic cough
- Avoid misuse or overdose
Drug Interactions
- MAO inhibitors (risk of serotonin syndrome)
- SSRIs and other serotonergic drugs
- Alcohol and sedatives (↑ CNS depression)
Pregnancy & Lactation
Generally considered low risk. Use only if clearly needed and under medical advice.
Key Notes
- No analgesic or anti-inflammatory action
- Not effective for productive (wet) cough
- Commonly combined with antihistamines or decongestants
References
- British National Formulary for Children (BNFc). Cough suppressants – Dextromethorphan.
- Kliegman RM, St. Geme JW. Nelson Textbook of Pediatrics, 22nd ed. Elsevier; Chapter: Cough and cold medications.
- Katzung BG, Trevor AJ. Basic & Clinical Pharmacology, 15th ed. McGraw-Hill; Drugs affecting the respiratory system.
- Manufacturer prescribing information.