Physostigmine poisons

Philippens IHCHM, Vanwersch RAP, Groen B, Olivier B, Bruijnzeel PLB, Melchers BPC. Subchronic physostigmine pretreatment in marmosets absence of side effects and effectiveness against soman poisoning with negligible postintoxication incapacitation. Toxicological Sciences 53 84-91, 2000a. 

Philippens IHCHM, Melchers BPC, Olivier B, Bruijnzeel PLB. Scopolamine augments the efficacy of physostigmine against soman poisoning in guinea pigs. Pharmacol. Biochem Behav. 65 175-182, 2000b. 

The nerve agenf analogy is not so far-fetehed. Physostigmine s only distinction from VX and other anticholinesterase poisons is that it is mueh less potent. Its relative lack of potency is the only thing that makes it impraetieal for use as a deadly chemical weapon. Like VX, physostigmine alone ean be lethal if one administers excessive dosage. 

The classic cholinesterase inhibitor is the alkaloid physostigmine (33), also called eserine. Investigations carried out in the nineteenth century on the ordeal poison esere, which consisted of an extract of the Calabar Bean, the seeds of Physostigma venenosum Balf, resulted in the isolation of (33)... 

Acute belladonna poisoning can be treated by administering universal antidote before gastric lavage, physostigmine in the dose of 1-A mg SC can be administered after a interval... 

Clinical anticholinesterases are mainly carbamates which have use for the treatment of conditions in which Ach stores are depleted or are ineffective. One, physostigmine, is a natural compound used in ancient judgement rituals in West Africa. To judge the veracity of an accused person, he was made to drink a brew made from the Calabar bean. If he got sick and vomited, thus eliminating the poison, he was innocent. If the stuff stayed down and he died, he was, of course, guilty. Physostigmine has an in vivo duration of inhbition of 3 to 4 hours. 

FIGURE 12—28. Icon for the cholinesterase inhibitor physostigmine. This agent is used intravenously as a short-acting cholinesterase inhibitor to reverse anticholinergic poisoning and is in testing in an oral sustained-release formulation for Alzheimer s disease. 

A third approach to protection against excessive AChE inhibition lies in pretreatment with reversible inhibitors of the enzyme to prevent binding of the irreversible organophosphate inhibitor. This prophylaxis can be achieved with pyridostigmine or physostigmine but is reserved for situations in which possibly lethal poisoning is anticipated, eg, chemical warfare. Simultaneous use of atropine is required to control muscarinic excess. 

Bonhage MR, Chilcoat CD, Li Q, Melendez V, Flournoy WS (2008) Evaluation of two scopolamine and physostigmine pre-treatment regimens against nerve agent poisoning in the dog. J Vet Pharmacol Ther 32 146-153... 

Hydroxybenzoate preservatives inactivate atropine sulfate in physical mixtures. Atropine can be used for treating acetylcholine poisoning. Organophosphorous pesticides are treated by use of diazepam, phenothiazines, and physostigmine.149... 

Jenner J, Saleem A, Swanston D. Transdermal delivery of physostigmine. A pretreatment against organophosphate poisoning./. Pharm. Pharmacol., 1995, 47(3), 206-212. 

Meshulam Y, et al. Prophylaxis against organophosphate poisoning by sustained release of scopolamine and physostigmine./. Appl. Toxicol., 2001, 21 (Suppl. 1), S75-S78. 

The literature on poisoning with tricyclic antidepressants has been reviewed and recommendations for the management of overdose proposed (SEDA-16, 8 156). In overdose, physostigmine can reverse life-threatening dysrhythmias, but its effect is short-lasting and it has adverse effects of its own it should be avoided (156). 

Alkaloids which activate neuromuscular action (so-called parasympa-thomimetics) include nicotine, arecoline, physostigmine, coniine, cytisine, and sparteine. Inhibitory (or parasympatholytic) alkaloids include hyoscy-amine and scopolamine, (see above) 312). Skeletal muscles as well as muscle-containing organs, such as lungs, heart, circulatory system, and gut, and the nervous system are certainly very critical targets. The compounds are usually considered to be strong poisons, and it is obvious that... 

Wetherell, J.R. (1994). Continuous administration of low dose ranges of physostigmine and hyoscine to guinea pigs prevents the toxicity and reduces the incapacitation produced by soman poisoning. J. Pharm. Pharmacol. 46 1023-38. 

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