I suffer from a condition called, Dysautonomia. It is the malfunction of the autonomic system. Your Autonomic system controls your blood pressure, heart rate, thyroid, your GI track, your breathing and most all of your organs. I am in the 2 % of how severe my condition is. A lot of people can take drugs and still work. As for me I worked too long. I kept collapsing and pushing myself at work till one day I collapsed and was never the same.