A patient came to the casualty with acute bronchial asthma after treatment for glaucoma. The probable drug may be -

Ans. is 'a' i.e., Timolol o As you all know b, receptors cause bronchodilatation, blockade of b, mediated bronchodilatation can precipitate bronchospasm and acute attack of asthma. o Timolol is a non-selective b -blocker (blocks pi and b 2 receptors). Therefore, it can precipitate acute attack of asthma. o Betaxolo is also a b -blocker. But it is a cardioselective b -blocker (blocks ft, receptors, not (32).