Antitussive Effect of a Naturally Flavored Syrup Containing Diphenhydramine, Compared With Dextromethorphan and Placebo

Summary

The purpose of this study is to evaluate the antitussive (cough-suppressing) effects of two liquid medications: a combination of diphenhydramine and phenylephrine in a naturally cocoa flavoring, and, dextromethorphan syrup, compared with placebo.

Timeline

Start

2014-01

Primary completion

2014-06

Completion

2014-06

Outcome

Met primary endpoint

paper with pairwise analysis revealing a significant increase in mean log C5 (0.4 ± 0.55 (SD); p < 0.01) for the diphenhydramine-containing medication versus placebo. PMID 25673148 ↗

paper Our results provide the initial evidence of the ability of diphenhydramine to inhibit cough reflex sensitivity in subjects with acute pathological cough. PMID 25673148 ↗

Publications

• Dicpinigaitis PV, Dhar S, Johnson A, Gayle Y, Brew J, Caparros-Wanderley W. Inhibition of cough reflex sensitivity by diphenhydramine during acute viral respiratory tract infection. Int J Clin Pharm. 2015 Jun;37(3):471-4. doi: 10.1007/s11096-015-0081-8. Epub 2015 Feb 12.

Drugs

Evaluation	Drug	Modality	Dose	Route
Subject	Dextromethorphan	Unknown	30 mg	Oral
Subject	Diphenhydramine	Small molecule	25 mg	Oral
Background	Phenylephrine	Small molecule	10 mg	Oral

Indications

No indication recorded.