Effectiveness of Guaifenesin in the Treatment of Cough

Cough results from a complex interaction between receptors in the airway and the central nervous system; this interaction is poorly understood. Glyceryl ether of guaiacol, commonly known as guaifenesin, is present in multiple cough and cold preparations. This compound has been labeled an expectorant because it is thought to relieve cough by thinning sputum and increasing its production. Guaifenesin is the only expectorant that has been considered effective by the U.S. Food and Drug Administration. Despite its broad use in the treatment of cough, multiple studies have found inconsistent results supporting the effectiveness of guaifenesin as an expectorant or cough suppressant. Little information is available concerning the impact of guaifenesin on the sensitivity of the cough reflex. Dicpinigaitis and Gayle conducted a randomized, placebo-controlled, double-blind study to assess the efficacy of a single dose of guaifenesin on cough reflex sensitivity.

The trial involved...