DEXTROMETHORPHAN

(Benylin DM, DM)

Standard Prescription

dextromethorphan__mg PO Q__H

Dosages

Children 6-12 years old:
5-10 mg/dose PO Q4H or 15 mg PO Q68H PRN
Maximum: 60 mg per day.

Children >=12 years old & Adults:
10-20 mg/dose PO Q4H or 30 mg PO Q68H PRN
Maximum: 120 mg/day.

Treatment of Methotrexate-Induced Leukoencephalopathy:
1-1.5 mg/kg/dose PO BID until symptom improvement
Maximum 60 mg/dose.

Mechanism of Action

Antitussive. Dextromethorphan is a prodrug of dextrorphan, the mediator of most of its dissociative effects, acting as a more potent NMDA receptor antagonist than dextromethorphan.  

Forms Supplied

syrup: 15 mg/5 mL

Comments

Studies in children have concluded that dextromethorphan is not superior to placebo in providing nocturnal symptom relief for children with cough and sleep difficulty as a result of upper respiratory infection.

Health Canada does not recommend the use of cough and cold products in children < 6 years of age.

May cause nausea, drowsiness.

Cough suppression may impair normal mechanism of pulmonary defense.

References

44, 133, 547

Last Edited

2022-06-19 05:22:11