Ethyl phosphorodimethylamido-cyanidate

GA is a volatile, liquid anticholinesterase nerve agents that reacts irreversibly with the enzyme cholinesterase, thereby permitting a deleterious accumulation of acetylcholine at nerve endings, which can lead to rapid death.

Tabun (GA) is a neurotoxic agent with an i.v. LD₅₀ in monkeys of 50 mg/kg and in rabbits of 63 mg/kg¹⁷.

GA causes runny nose, tightness of chest, dimness of vision and pinpointing of the eye pupils, difficulty in breathing, drooling and excessive sweating, nausea, vomiting, cramps, involuntary defecation and urination, twitching, jerking and staggering, headache, drowsiness, coma and convulsions, followed by cessation of breathing and death.