Physostigmine

Physostigmine is an anticholinesterase drug and it is used in treating glaucoma. For patients with glaucoma, a rise in intraocular pressure is usually found. Physostigmine can block the action of acetylcholinesterase, reducing disintegration of acetylcholine. There is a higher availability of acetylcholine for supporting neurotransmission in the parasympathetic nervous system, which promotes contraction of smooth muscle in the ciliary body. This results in an increase in outflow of aqueous humor by widening Schlemm’s canal and the trabecular meshwork, lowering the intraocular pressure of patients with glaucoma. The use of Physostigmine may bring about several adverse effects, such as an increased spasm of accommodation and cramps in the intestines.