How often can I take Tussin (dextromethorphan)?

Dextromethorphan (Tussin) Dosing Frequency

For adults, dextromethorphan should be taken as 20-30 mg every 4-6 hours, with a maximum daily dose not exceeding 120 mg per day. 1, 2

Standard Dosing Recommendations

Adults

• Single dose: 20-30 mg 2, 3
• Frequency: Every 4-6 hours as needed 1
• Maximum daily dose: 120 mg per day (typically 4 doses of 30 mg) 2
• Studies demonstrate that a single 30 mg dose provides reproducible cough suppressant effects with objective reduction in cough counts and intensity 2

Pediatric Patients

• Dextromethorphan has been used safely in children for over 30 years 1
• The safety profile in pediatric overdose is reassuring, though specific pediatric dosing should follow product labeling 1

Clinical Efficacy Evidence

Dextromethorphan at 20 mg doses has been shown to be as effective as codeine for cough suppression, with superior tolerability. 3

• In comparative trials, 20 mg dextromethorphan reduced cough frequency similarly to 20 mg codeine 3
• Dextromethorphan lowered cough intensity significantly more than codeine (p < 0.0008) 3
• The majority of patients preferred dextromethorphan over codeine (p < 0.001) 3

Safety Considerations

Adverse Effects

• Adverse drug reactions are infrequent and usually not severe when used at recommended doses 1
• Dose-related symptoms may include neurological, cardiovascular, and gastrointestinal disturbances 1
• The drug has a reassuring safety profile, particularly regarding overdose in both adults and children 1

Critical Drug Interactions

Do not use dextromethorphan with monoamine oxidase inhibitors (MAOIs). 1

• Coadministration of MAOIs and dextromethorphan represents a significant safety concern 1
• This combination can result in serious adverse events 1

Abuse Potential

• The most significant hazard identified through adverse event reporting is episodic and sporadic abuse 1
• Despite this concern, when used appropriately for short-term treatment, dextromethorphan maintains a favorable safety profile 1

Duration of Treatment

• Dextromethorphan is intended for short-term symptomatic relief of cough 1
• The pharmacokinetic polymorphism observed with dextromethorphan does not correlate with clinically significant safety risks during short-term use 1
• Objective cough suppression effects occur within hours of a single dose and persist for the dosing interval 2