Organophosphate antidote

Obidoxime is an antidote used to treat poisoning with insecticides of the organophosphate type (p. 102). Phosphorylation of acetylcholinesterase causes an irreversible inhibition of ace-Ltillmann, Color Atlas of Pharmacology 2000 Thieme All rights reserved. Usage subject to terms and conditions of license. 

Zvlrblis, P., Ellin, R.I. 1982. Kinetics and stability of a multicomponent organophosphate antidote formulation in glass and plastic. J. Pharmaceut. Sci. 71 311-325. 

Antidotes that remove active poison from its site of action e.g. hydroxylamine used in organophosphate anticholinesterase poisoning. 

Still another experimental route to introducing otherwise excluded molecules into the brain is to chemically modify them so that they are lipophilic and therefore can passively diffuse. The brain, just as most other organs and tissues of the body, has enzymes to metabolize or biotransform metabolites in order to use and then get rid of them. Many of these pathways are oxidative. A reduced species or derivative which is lipophilic can enter the brain by simple passive diffusion there to be oxidatively transformed into an active state. Compounds which have been tested in animals include derivatives of 2-PAM (an antidote for organophosphate insecticide poisoning) and phenylethylamine (similar to amphetamine type molecules). Figure 5 illustrates the general concept behind this method. 

Atropine is an "antidote" to poisoning by excessive stimulation of cholinergic muscarinic receptors such as occurs in mucarine and organophosphate insecticide poisoning. 

Functional interactions are those in which both of the two chemicals affect a bodily system perhaps by different mechanisms, and either increase or decrease the combined effect. For example, both atropine and pralidoxime decrease the toxic effects of organophosphate compounds by different means, a combination of the two antidotes leads to a large increase in effectiveness synergism). 

Depending on the specific organophosphate, some phosphorylated enzyme may be reactivated ("dephosphorylated") by certain oxime antidotes from one to two days after OP absorption. Thereafter a change in the nature of the enzyme-phosphoryl bond occurs, rendering the inactivation irreversible and necessitating the generation of new enzyme. 

AChE, BChE (carbamoylates active site Serine) [anti-AD, esp. AD amyloid plaque- tangle-associated ChE miotic, organophosphate poison antidote, parasympathetic, toxic]... 

Atropine is the recommended antidote for organophosphate and carbamate insecticide poisoning. It competes with acetylcholine for the active site of the acetylcholine... 

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