Drug contraindicated in glaucoma patient suffering from bronchial asthma:
Ans. (a) TimololRef. KDT 6th ed./144LATANOPROSTMOA: Increase of aqueous humor outflowSide effects: Red eye and ocular irritation, increased iris pigmentation, and excessive hair growth of eye lashes.* Timolol is a prototype of ocular b blockers. It is a non selective beta blocker (blocks b1+b2) and has no anesthetic or intrinsic sympathomimetic activity.* Timlols ocular hypotesive action (20-35% fall in I.O.T.) is smooth and well sustained.* Lungs have b2 receptor, and if they are blocked in case of asthmatic patient, the condition worsens. Therefore non selective beta blockers are always avoided in case of asthmatic patients.* Betaxolol is a b1 selective blocker, offering the advantage of less bronchopulmonary and probably less cardiac, central and metabolic side effects.* Betaxolol is less effective in lowering IOT than timolol, because ocular beta receptors are predominantly of b2 subtype.* Acetazolamide is a carbonic anhydrase inhibitor which reduces the aqueous formation by limiting generation of bicarbonate ion in ciliary epithelium.* Latanoprost is a prostaglandin analogue. It is a PGF2a analogue which act by increasing uveoscleral outflow.
Timolol
Betaxolol
Acetazolamide
Latanoprost
Anti Adrenergic System