EC Pharmacology and Toxicology

Organophosphate (OP) compounds are used as insecticides in agriculture, animal care and pest control in living areas. Organophosphate poisoning remain as a serious public health problem due to its easy-availability and high-solubility. These compounds exhibit their toxic properties by inhibiting acetylcholinesterase enzyme in erythrocyte membranes, skeletal muscle and nerve tissue. This inhibition results in the clinical picture called “cholinergic crisis”. Since acetylcholinesterase is inhibited, acetylcholine (ACh) accumulates in the synaptic junctions and neurotransmission in the central and peripheral nervous system deteriorates. This deterioration results in life-threatening cholinergic crisis and intermediate syndrome. Also, acetylcholinesterase (AChE) activity blockage leads to stimulation of nicotinic receptors. In treatment, while atropine (anticholinergic) is used for reversal of cholinergic effects, oximes (cholinesterase reactivator) are used for neurological manifestations. Atropine blocks the effect of ACh on muscarinic receptors and terminates parasympathetic stimuli. On the other hand, oximes reverses the nicotinic effects and restores active cholinesterase. Oximes also dealklates and reactivates AChE by removing the phosphoryl group on AChE where the OP binds. However, in some instances, conventional supportive therapy along with atropine and oximes fail. In such cases some novel treatment methods are needed. In this narrative review, we aimed to evaluate novel methods such as hemoperfusion, hemodyalisis, plasma exchange and intravenous lipid emulsion therapy with pros and cons in the light of current literature. We also aimed to make some suggestions on where and how to use them.

 Keywords: Organophosphate Poisoning; Treatment; Hemoperfusion; Hemodyalisis; Intravenous Lipid Emulsion

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