Antidotes antimuscarinic

A number of drugs in addition to atropine and scopolamine have antimuscarinic properties. Tbese include tricyclic antidepressants, phenothiazines, and antihistamines. Physostigmine has been used in the treatment of acute toxicity produced by these compounds. However, physostigmine can produce cardiac arrhythmias and other serious toxic effects of its own, and therefore, it should be considered as an antidote only in life-threatening cases of anticholinergic drug overdose. 

Atropine Nonselective competitive antagonist at all muscarinic receptors in CNS and periphery Blocks muscarinic excess at exocrine glands, heart, smooth muscle Mandatory antidote for severe cholinesterase inhibitor poisoning Intravenous infusion until antimuscarinic signs appear continue as long as necessary Toxicity Insignificant as long as AChE inhibition continues... 

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