Chapter 9: Physiological Factors (Including Drugs and Alcohol) Affecting Pilot Performance  easily. A small amount of fluid in the mouth turns this mechanism off and the replacement of  needed body fluid is delayed. Other steps to prevent dehydration include: Heatstroke is a condition caused by any inability of the body to control its temperature. Onset of  this condition may be recognized by the symptoms of dehydration, but also has been known to be  recognized only upon complete collapse.  To prevent these symptoms, it is recommended that an ample supply of water be carried and used  at frequent intervals, whether thirsty or not. The body normally absorbs water at a rate of 1.2 to 1.5  quarts per hour. Individuals should drink one quart per hour for severe heat stress conditions or one  pint per hour for moderate stress conditions. For more information on water consumption, refer to  the “Dehydration” section of this chapter.  The Federal Aviation Regulations include no specific references to medication usage. Title 14 of the  CFR prohibits acting as PIC or in any other capacity as a required pilot flight crewmember, while that  person:  Further, 14 CFR part  107 and 14 CFR part 91, sections 91.17 and 91.19 prohibit the use of any drug  that affects the person’s faculties in any way contrary to safety. There are several thousand medications currently approved by the U.S. Food and Drug  Administration (FDA), not including OTC drugs. Virtually all medications have the potential for  adverse side effects in some people. Additionally, herbal and dietary supplements, sport and energy  boosters, and some other “natural” products are derived from substances often found in  medications that could also have adverse side effects. While some individuals experience no side  effects with a particular drug or product, others may be noticeably affected. The FAA regularly  reviews FDA and other data to assure that medications found acceptable for aviation duties do not  pose an adverse safety risk. Some of the most commonly used OTC drugs, antihistamines and decongestants, have the potential  to cause noticeable adverse side effects, including drowsiness and cognitive deficits. The symptoms  associated with common upper respiratory infections, including the common cold, often suppress a  pilot’s desire to fly, and treating symptoms with a drug that causes adverse side effects only  compounds the problem. Particularly, medications containing diphenhydramine (e.g., Benadryl) are  Remote Pilot – Small Unmanned Aircraft Systems Study Guide  48 1. Knows or has reason to know of any medical condition that would make the person unable to  meet the requirement for the medical certificate necessary for the pilot operation, or 2. Is taking medication or receiving other treatment for a medical condition that results in the  person being unable to meet the requirements for the medical certificate necessary for the  pilot operation. • Carrying a container in order to measure daily water intake. • Staying ahead—not relying on the thirst sensation as an alarm. If plain water is not preferred,  add some sport drink flavoring to make it more acceptable. • Limiting daily intake of caffeine and alcohol (both are diuretics and stimulate increased  production of urine). Heatstroke  Drugs 