U.S. Code of Federal Regulations

Regulations most recently checked for updates: Oct 31, 2025

§ 338.10 - Nighttime sleep-aid active ingredients.

The active ingredient of the product consists of any of the following when used within the dosage limits established for each ingredient in § 338.50(d):

(a) Diphenhydramine hydrochloride.

(b) Diphenhydramine citrate.