Atropine is used as an antidote against nerve agents, like

• Tabun (GA),
• Sarin (GB),
• Soman (GD)
• & VX

which block the nervous system’s “off” message to muscles, resulting in extremely painful muscle spasms & finally death due to a breakdown of the respiratory system. Atropine counters this by restoring the “off” message to the muscle systems. Usually atropine would be injected into the leg with the use of an autoinjector.

By blocking the action of acetylcholine at muscarinic receptors, atropine also serves as an antidote for poisoning by organophosphate insecticides & nerve gases. Troops who are likely to be attacked with chemical weapons often carry autoinjectors with atropine & obidoxime which can be quickly injected into the thigh. Atropine is often used in conjunction with Pralidoxime chloride.

Atropine is given as an antidote to SLUDGE:

• Salivation,
• Lacrimation,
• Urination,
• Diaphoresis,
• Gastrointestinal motility,
• Emesis)

symptoms caused by organophosphate poisoning.

Some of the nerve gases attack & destroy acetylcholinesterase, so the action of acetylcholine becomes prolonged. Therefore, atropine can be used to reduce the effect of acetylcholine.

(g-spot, wikipedia.org )