OTC MENTHOL NEEDS MULTIPLE DOSE STUDY TO SUPPORT DECONGESTANT USE
Executive Summary
OTC MENTHOL NEEDS MULTIPLE DOSE STUDY TO SUPPORT DECONGESTANT USE, FDA told Smith-Kline Beecham in a recent letter. Responding to a petition from Beecham to include 10 mg menthol in the final monograph for OTC nasal decongestants, FDA said that "another study involving multiple doses is needed to support effectiveness." The petition was submitted on Feb. 10, 1988. FDA said that the study should "be done using the same dosage and given at the same time intervals as proposed for label directions" (the company proposed a 10 mg lozenge taken every two hours as needed). A "three-day study," FDA said, "is necessary to show effectiveness as a nasal decongestant if indicated for colds and seven days if indicated for allergies." The agency also suggested that the study look at the potential for rebound congestion. FDA noted that SmithKline Beecham's petition "will not be addressed in the final monograph...because the final monograph for OTC nasal decongestant drug products may [be published] prior to resolution of the...discussed issues." In support of the requested inclusion of menthol in the monograph, Beecham had submitted one study using a single dose of menthol. Results of the study, FDA said, were "supportive of the effectiveness of a 10 mg menthol lozenge," but "not sufficient to reclassify the ingredient from Category III to Category I." In addition to its traditional two-study requirement, the agency cited the fact that the study did not evaluate the multiple dose regimen proposed by the company ("every two hours as needed"). The submitted study measured nasal flow/resistance at 15, 30, 60, 90 and 120 minutes after treatment with a 10 mg menthol lozenge. Results, FDA said, "support a two-hour duration of action from a single dose." The agency reported that the study found a "negligible change from baseline" in subjects that received placebo, whereas "menthol reduced nasal flow/resistance 1.00 to 1.57 cm H20/L/sec over the interval 15 minutes to 120 minutes." * Menthol is the active ingredient in SmithKline Beecham's N'ICE lozenges. The ingredient is also contained in a number of other OTC cold products, including Rich-Vicks' Vicks cough drops and throat lozenges, Marion Merrell-Dow's Cepastat lozenges, and Warner-Lambert's Halls Mentho-Lyptus cough drops.