Demecarium bromide, trade name Humorsol, is a carbamate parasympathomimetic drug that acts as an acetylcholinesterase inhibitor, and is used as a glaucoma medication. It is applied directly to the eye in order to reduce elevated intraocular pressure associated with glaucoma. Demecarium causes constriction of the pupil (miosis), which improves the drainage of the fluid in the eye (aqueous humour). As demecarium reversibly inhibits cholinesterase, it can be administered less frequently than other parasympathomimetic drugs, such as carbachol.