Miotic agent used in glaucoma:

(Ref: KDT 8th ed. pg. 167)Pilocarpine is a directly acting parasympathomimetic (cholinergic) drug which acts mainly on pupil (M3) causes miosis.Reduces IOP within few minutes and lasts for upto 4-8 hrsHence used in Glaucoma (OAG) patients.Methacholine is a directly acting parasympathomimetic (cholinergic) drug which acts mainly on myocardium (M2) causing bradycardia. Hence used to treat tachycardia and can also be used to diagnose bronchial hyperactivity (methacholine challenge test).# Half-life: > 2 hoursBethanechol is directly acting parasympathomimetic (cholinergic) drug which works on bladder (M3) and is used in acute urinary retention/Atonic bladder.# Half-life: 2 hoursCevimeline is recently approved drug used for xerostomia in sjogren syndrome or for patients undergoing chemotherapy.