CFR › Title 21 › Part 336 › §336.1021 CFR §336.10Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗Copy linkThe active ingredient of the product consists of any of the following when used within the dosage limits established for each ingredient in § 336.50(d):(a)Cyclizine hydrochloride.(b)Dimenhydrinate.(c)Diphenhydramine hydrochloride.(d)Meclizine hydrochloride.