###Rationale: (Decreases aquous formation): Ref: 222-KH, 87-KDTMechanism of actions of beta-adrenergic blockersTimolol and levobunolal are non selective beta 1 (Cardiac) and beta 2 (smooth muscle, pulmonary) receptor blockers, causes lower IOP by blockade of beta - 2 rceptors in the ciliary process resulting in decreased aquous production.* Betaxolol are thought to increase the perfusion of the optic nerve head (305-P) cardio selective* Metipranolol: only in preservative free units, it is therefore useful in patients allergic to preservatives or wearing soft contact lens (in whom benzolkonium chloride should be avoided)Mode of action of ocular hypotensive drugs (87-KDT)Drugs/classAqueous secretionTrabecular outflowUveoscleral outflow1. b-blockers (Timolol)|----2. Miotics (Pilocarpine)--|--3. Adrenal ine/Dipi ve fri ne|?||4. Brimonidine/Apraclonidine|--|?5. Prostaglandins (latanoprost--|?|6. Carbonic anhydrase inhibitors|----

###Answer: OPTION C IS CORRECT.
###Question: Mechanism of action of beta-blockers in glaucoma is
###Options:
A. Increases uveo-scleral out flow of aqueous
B. Increases trabecular mesh work out flow
C. Decreaes aqueous production
D. Constant aqueous production in ciliary body
