Ans. c. Levobunolol Brimonidine, dorzolamide and prostaglandin are topical anti-glaucoma drugs. These drugs do not have systemic side effects, while levobunolol (beta-blocker) is systemic anti-glaucoma drug given orally, having systemic side effects. That is why in patients with glaucoma treated with systemic beta blockers, levobunolol may add on the side effects of beta-blockers, hence avoided in the above mentioned patient. Topical Anti-glaucoma Drugs Adrenergic agonist Non-selective: Epinephrine, Dipivefrine Alpha2-selective: Apraclonidine, Brimonidine Adrenergic antagonist Beta--blocker (Non-selective): Timolol, Levobunolol, Caeolol, Metipranolol, Adapralol Betal-blocker: Betaxolol Miotics (direct parasympatomimetics) Pilocarpine, Physostigmine Ecothiophate, Carbachol, Demacarium Prostaglandin analogues Latanoprost Carbonic anhydrase inhibitors Dorzolamide Systemic Antiglaucoma Drugs Carbonic anhydrase inhibitors Acetazolamide Dichlorphenamide Methazolamide Hyperosmotic agents Mannitol Glycerol