Comparative Pharmacology
Head-to-head clinical analysis: ANTITUSSIVE versus VICKS FORMULA 44.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ANTITUSSIVE versus VICKS FORMULA 44.
ANTITUSSIVE vs VICKS FORMULA 44
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Antitussives suppress cough by acting on the cough center in the medulla oblongata (central antitussives) or by anesthetizing stretch receptors in the respiratory tract (peripheral antitussives).
VICKS FORMULA 44 contains dextromethorphan (NMDA receptor antagonist and sigma-1 receptor agonist; suppresses cough by acting on the medullary cough center) and doxylamine (first-generation antihistamine; H1-receptor antagonist; anticholinergic and sedative effects).
For dextromethorphan: 10-20 mg orally every 4-6 hours, maximum 120 mg/day. For codeine: 10-20 mg orally every 4-6 hours, maximum 120 mg/day.
VICKS FORMULA 44 is a combination product containing dextromethorphan (cough suppressant) and doxylamine (antihistamine). The typical adult dose is 30 mg dextromethorphan/6.25 mg doxylamine (15 mL) orally every 6 hours as needed for cough and cold symptoms, not to exceed 4 doses per 24 hours.
None Documented
None Documented
Terminal elimination half-life is 3-6 hours in adults; prolonged in renal impairment (up to 12-18 hours).
Dextromethorphan: 3-6 hours (extensive metabolizers), up to 24 hours (poor metabolizers); doxylamine: 10-12 hours. Clinically, half-life may be prolonged in elderly, hepatic impairment, or CYP2D6 poor metabolizers.
Renal excretion of unchanged drug and metabolites (primarily glucuronide conjugates) accounts for approximately 60-80% of elimination, with biliary/fecal excretion contributing 15-25%.
Renal excretion of unchanged drug and metabolites (dextromethorphan and doxylamine): dextromethorphan is extensively metabolized; <10% excreted unchanged. Doxylamine: ~60% excreted renally as unchanged and metabolites.
Category C
Category C
Antitussive
Antitussive