Diphenhydramine hydrochloride (/[unsupported input]ˌdaɪfɛnˈhaɪdrəmiːn/; abbreviated DPH, sometimes DHM) is a first-generation antihistamine possessing anticholinergic, antitussive, antiemetic, and sedative properties which is mainly used to treat allergies. Like most other first-generation antihistamines, the drug also has a powerful hypnotic effect, and for this reason is often used as a non-prescription sleep aid. It is produced and marketed under the trade name Benadryl by McNeil-PPC (a division of Johnson & Johnson) in the U.S., Canada and South Africa (other trade names in other countries: Dimedrol, Daedalon). It is also available as a generic or store brand medication. It is also found in the name-brand products Nytol, Unisom, Tylenol PM, Excedrin PM, Midol PM and Advil PM, though so