Cholinergic agents seizures caused

The main toxic effect of the OPs is the inhibition of the acetylcholine esterase (AChE) in the synapses and neuromuscular junctions, causing cholinergic crisis, which eventually leads to seizures, respiratory arrest and death. There are considerable differences in the dynamic of clinical manifestations and impairment induced by nerve agents and OP insecticides (slower onset, dependent on metabolic activation, prolonged effect based on their accumulation in certain tissues and subsequent systemic release). 

Nerve agents such as tabun (GA), sarin (GB), soman (GD), and VX inhibit acetylcholinesterase enzyme throughout the body, notably in the nervous system. This causes hyperactivation of cholinergic pathways, causing convulsive seizures and respiratory failure. VX differs from its G agent counterparts in its low volatility. 

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