Pralidoxime acts by -

Ans. is 'a' i.e., Reactivating cholinesterase enzyme o Pralidoxime is most commonly used cholinesterase reactivater.OXIMESo Oximes 1 Pralidoxime 2-PAM, obidoxime and diacetyl-monoxime (DAM)J are used in organophosphatepoisoning.o Oximes acts by reactivating cholinesterase enzyme.o Mechanism of actionIn organophosphate poisoning esteratic site of cholinesterase is phosphorylated and anionic site is free.Phosphorylated cholinesterase reacts very slowly with water.However, if more reactive OH groups in the form of oximes are provided, reactivation occurs more than a million time faster.Oximes attach to anionic site and provide more reactive OH groups.Oximes are ineffective in Carbamates poisoning.Pralidoxime is contraindicated in carbamates poisoning, because not only it does not reactivate carbamylated enzyme, it has weak anti-chE activity of its own.Remembero Obidoxime is more potent than pralidoxime.o Pralidoxime and obidoxime are lipid insoluble, while diacetyl-monoxime (DAM) is lipid soluble so it can cross EBB and regenerate AChE in brain.o Atropine is used in both organophosphate and carbamate anticholinesterase poisoning.