<prompt> An old patient Ram Kishore having asthma and glaucoma is to receive a b blocker. Regarding b blocking drugs:Metoprolol blocks b2 receptors selectivelyEsmolols pharmacokinetics are compatible with chronic topical useNadolol lacks b2 blocking actionTimolol lacks the local anaesthetic effects of propanolol  <response>: Metoprolol is a cardioselective b1 selective blocker and not b2 selective. Esmolol is the shoest acting b -blocker and is useful for acute treatment. Nadolol is a non-selective b-blocker. It blocks both b1 as well as b2 receptors. Propanolol possesses maximum local anaesthetic activity whereas timolol lacks this propey. 