Summarize Nerve agents are highly toxic and rapidly affect exposed individuals. Nerve agents enter the body primarily through the respiratory tract, although they may be absorbed through the eyes or skin. In the liquid state, nerve agents are hazardous via skin or eye contact and through ingestion. Generally, all nerve agents are highly toxic and fast acting. When a person is exposed to a nerve agent, the nerve agent, upon entering the body, inhibits the normal actions of acetylcholinesterase; a chemical within the body whose normal function it is to break down the chemical acetylcholine. Acetylcholine causes muscular contraction. What nerve agents do to acetylcholinesterase is inhibit it from breaking down acetylcholine which in turn causes violent muscle spasms. What are the symptoms of nerve agent poisoning? When an individual is exposed to low amounts of a nerve agent (as a gas or aerosol) the initial symptoms are a runny nose, contraction of the pupils, deterioration of visual accommodation, headache, slurred speech, nausea, hallucinations, pronounced chest pains, and an increase in the production of saliva. At higher doses, these symptoms are more pronounced. Coughing and breathing problems also begin to occur. The individual then may begin to go into convulsions