Oswald in the doorway: the blog of the Oswald Innocence Campaign, by Ralph Cinque

This is a very good and concise description of nerve agents from the Argon site.

 The history of nerve agents

The earliest weaponized form of nerve agent is Tabun which was synthesized by a team of German scientists, led by Gerhard Schrader, on the eve of the Second World War. Its discovery was an accidental by-product of research into the use of insecticides.

The principal nerve agents are sarin (GB), soman (GD), tabun (GA) and VX.According to the US, the VX nerve agent was the chemical used to kill the half-brother of Kim Jong-un in 2017.

Exposure to nerve agents

Nerve agents are easily absorbed via the respiratory tract. Victims can experience symptoms, such as runny nose and tightness in the chest or throat, within seconds or minutes after exposure.

In liquid form, nerve agents are readily absorbed via the skin and eyes. Vapers won't be absorbed through the skin unless in very high concentrations. Ocular effects can result due to both direct contact and systemic absorption.

The timing and nature of symptoms following dermal contact with a liquid nerve agents depends upon the exposure dose. In some cases the effects may be delayed for up to 18 hours.

Ingestion of nerve agents is a relatively rare occurrence compared to skin contact or inhalation, however, they are readily absorbed through the gastrointestinal (GI) tract, with highly toxic effect.

Symptoms of nerve agent exposure

One of the first symptoms of nerve agent exposure is miosis - excessive constriction of the pupil of the eye.

Other major symptoms include convulsions, loss of consciousness, excessive fluid secretion of the lungs, high blood pressure, raised heart rate (and then later, lowered heart rate), nausea and vomiting.

RC: So, notice that it says that nerve agents are exposed easily through the skin. And they are referring to just getting the nerve agent on the intact skin and having it soak in. In JFK's case, we are talking about a missile that pierced his skin. And then, it says that other major symptoms include convulsions. A convulsion is an abnormal and involuntary contraction of skeletal muscles. And that is exactly what we are seeingon Kennedy. His arms were in spasm, and he couldn't put them down. Jackie even tried to get him to put his arms down, but to no avail. She pressed on his arm, which was her trying to get him to put his spasmodic arm down. He couldn't do it, and she couldn't do it for him. 

If you look at these images from another post, you'll see what I mean, that JFK was stuck in a spasmodic state, and he couldn't do a thing about it. 

https://oswaldinthedoorway.blogspot.com/2020/04/this-is-letter-i-sent-to-some-doctor.html