Low esterase levels are suggestive of overdose of some drug which acts by inhibiting acetyl choline esterase like organophosphate poisoning. Inhibition of choline esterase results In increased amount of Ach at synapse, so poisoning or overdose results in cholinergic symptoms like salivation, lacrimation, urination, emesis, increased bronchial secretions, reduction in blood pressure.So treatment Of choice is Atropine. Atropine -It is highly effective in counter-acting the muscarinic symptoms, but higher doses are required to antagonize the central effects. It does not reverse peripheral muscular paralysis which is a nicotinic action. All cases of anti-ChE (carbamate or organophosphate) poisoning must be promptly given atropine2 mg i.v. repeated every 10 min till dryness of mouth or other signs of atropinization appear (upto 200 mg has been administered in a day). Continued treatment with maintenance doses may be required for 1-2 weeks. Neostigmine and physostigmine worsens the signs and symptoms as these also act by inhibiting choline esterase. Physostigmine and flumazenil are respectively used for Atropine and benzodiazepines poisoning.