The body takes care of itself naturally but when placed in an environment where it cannot do this it becomes unable to function properly. To deal with this, pilots tend to use stimulants which are a short time remedy. This tends to very dangerous for them and their clients or co-workers yet it can be avoided. The other problem is that they self-diagnose, treat and prescribe for themselves medication that may not be appropriate for their working conditions.
In the book “Basic Flight Physiology” (Reinhart R. O. 1996), the author discusses different scenarios that a pilot can find him or herself in that can affect the physiological balance causing malfunctions of the body and brain. In chapter 9 of the book, he starts with an example of Joe whose lack of sleep coupled with the use of coffee and cigarettes almost causes him to have an accident. He is impaired due to the overuse of the body beyond its normal capacity and hence the body rebels. He acknowledges that some conditions are caused by environmental factors but that some are man-made.
Self Imposed Stress Definition
It is important to note that the flight environment is different from the ground environment and hence medication that can be used safely while on the ground may have a different effect when used in a flight environment causing self-imposed medical stresses. These can be summed up in the acronym DEATH (Drugs Exhaustion Alcohol Tobacco and Hypoglycemia). Although there are other causes of stress like problematic relationships, these are the major ones. The effects of the use and presence of any of these factors depends on an individual and this leads to controversy over how much they affect the physiological wellbeing of a pilot.