Propoxyphene hydrochloride is an odorless, white crystalline powder with a bitter taste. It is freely soluble in water. Chemically, it is alpha (+)-4-(Dimethylamino)-3-methyl-1,2-diphenyl-2-butanol Propionate Hydrochloride.

Darvon contains propoxyphene hydrochloride, USP which is an odorless, white crystalline powder with a bitter taste. It is freely soluble in water. Chemically, it is (2S,3R)-(+)-4-(Dimethylamino)-3-methyl-1,2-diphenyl-2-butanol propionate (ester) hydrochloride, which can be represented by the accompanying structural formula. Its molecular weight is 375.94.

Darvocet-N contains propoxyphene napsylate and acetaminophen.