Meta-analysis of the efficacy of a single dose of phenylephrine 10 mg compared with placebo in adults with acute nasal congestion due to the common cold

Abstract

Background Although nonprescription oral phenylephrine 10 mg has been judged "generally recognized as safe and effective" by the US Food and Drug Administration (FDA), its efficacy as a nasal decongestant has been questioned. Objective This study assessed available data on the efficacy of oral phenylephrine 10 mg as a nasal decongestant. Methods Three sources were used to identify potentially relevant publications--the bibliography of the phenylephrine section of the 1976 FDA monograph on over-the-counter cold, cough, allergy, bronchodilator, and antiasthmatic products; a 2004 Cochrane Review of nasal decongestants for the common cold; and a search of MEDLINE from 1966 through January 2007 using the term phenylephrine nasal. To be included in the analyses, studies had to have a single-dose, randomized, placebo-controlled design; involve an orally administered product in which phenylephrine 10 mg was the sole active ingredient; enroll patients with acute nasal congestion due to the common cold; evaluate nasal airway resistance (NAR) as the efficacy end point; and have sufficient data in the study report to allow reanalysis and/or meta-analysis of phenylephrine 10 mg versus placebo. Reanalysis of individual studies and fixed-effects and random-effects meta-analyses were performed. Statistical significance at 30 and 60 minutes after dosing (the primary time points) and a >or=20% reduction in NAR from baseline were considered indicative of a clinically meaningful difference. Resu…