<prompt> Effects of d-tubocurarine are reversed by?AtropineNeostigmineSuccinylcholineBarbiturates  <response>: Ans. is b i.e., Neostagmine d-tubocurarine is a non-depolarizing blocker. For reversal of non-depolarizing blocker, anticholinesterases are used. They increase the concentration of Ach by inhibiting its degradation by cholinesterase. Most commonly neostigmine is used. Other drugs are edrophonium, Pyridostigmine, Physiostigmine. Atropine is given to prevent muscarinic side effects of neostigmine it does not cause reversal.Remember Neostigmine does not antagonise depolarising blockers Therefore cannot be used for reversal. Infact neostigmine can potentiate the block as neostigmine and other anti- cholinesterase also inhibits pseudocholinesterase which metabolizes Sch. 