Demecarium

**Semantic type:** Pharmacologic Substance

**Definition:** A quaternary ammonium compound that serves as a long-acting cholinesterase inhibitor with parasympathomimetic activity. When used topically, demecarium inactivates both pseudocholinesterase and acetylcholinesterase, thereby preventing acetylcholine breakdown and increasing acetylcholine activity. This causes contraction of the iris sphincter muscle (producing miosis) and the ciliary muscle (affecting the accommodation reflex). In so doing, this agent increases the outflow of the aqueous humor, thereby reducing intraocular pressure.

**Synonyms:** - (M-Hydroxyphenyl)Trimethylammonium Decamethylenebis(Methylcarbamate) - 3,3'-(1,10-Decanediylbis((Methylimino)Carbonyloxy))Bis(N,N,N-Trimethylbenzenaminium) - Benzenaminium, 3,3'-(1,10-Decanediylbis((Methylimino)Carbonyloxy))Bis(N,N,N-Trimethyl)- - DEMECARIUM - N,N'-Bis(3-Trimethylammoniumphenoxycarbonyl)-N,N'-Dimethyldecamethylenediamine