A patient with a recent history of convulsions, presented to emergency in subconscious state with blood pressure 60/90 mm/Hg, bradycardia & slow gasping respiration. There is increased lacrimation, salivation & sweating. On examination there is pin point pupil. Which of the following poisoning should be suspected?

Ans. is 'c' i.e., Organophosphorus [Ref Parikh 6Th /e p. 10.43; Reddy 33`d% p. 5231Organophosphorus poisoning compounds are irreversible inhibitors of enzyme cholinesterase, an enzyme which hydrolyzes acetylcholine.Thus organophosphates inhibit cholinesterase and protect acetylcholine from hydrolysis. This results in increased concentration of acetylcholine and excessive cholinergic activity.They inhibit cholinesterase by phosphorylating the catalytic site of enzyme. Less than 50% of cholinesterase activity is indicative of poisoning.Clinical features of poisoning are due to excessive cholinergic activity. Local muscarinic manifestations at the site of exposure (skin, eye, GIT) occur immediately and are followed by complex, systemic effects due to muscarinic, nicotinic and central actions