<unk>  is a drug that acts as a muscarinic receptor agonist. It acts on a subtype of muscarinic receptor (M3) found on the iris sphincter muscle, causing the muscle to contract - resulting in pupil constriction (miosis).<unk>  also acts on the ciliary muscle and causes it to contract. When the ciliary muscle contracts, it opens the trabecular meshwork through increased tension on the scleral spur. This action facilitates the rate that aqueous humor leaves the eye to decrease intraocular pressure. Paradoxically, when<unk>  induces this ciliary muscle contraction (known as an accommodative spasm) it causes the eye's lens to thicken and move forward within the eye. This movement causes the iris (which is located immediately in front of the lens) to also move forward, narrowing the Anterior chamber angle. Narrowing of the anterior chamber angle increases the risk of increased intraocular pressure.
Pilocarpine
Timolol
Avacopan
Ibotenic acid
Tropicamide
Dihydroergotamine
Oxymetazoline
Beclamide