On December 12, 2002, at 1530 eastern daylight time, a Stinson 108-1, N8469K, piloted by a private pilot, was destroyed on impact with terrain approximately 1/2 mile southeast of Zehnder Field (66G), Frankenmuth, Michigan. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 personal flight was not operating on a flight plan. The pilot was fatally injured. The local flight originated from 66G about 1528. Witness reported that the airplane departed 66G and climbed to an altitude of about 200 feet above ground level, turned left toward a southeasterly heading for about 3/4 mile while maintaining level flight, and then entered a left bank turn and impacted a tree and terrain. The on-scene investigation was performed by inspectors from the Federal Aviation Administration's (FAA) Grand Rapids Flight Standards District Office. The airplane was resting inverted about 0.9 statute miles on a magnetic heading of 147 degrees from 66G. The fuselage was bent forward between the empennage and cabin. There was no lateral displacement of the empennage. The wings and stabilizers were attached to the fuselage. Ground scarring was limited the area beneath the airframe. Examination of the wreckage revealed that the throttle control was 3/4 travel forward position and the mixture control was at the forward stop. Flight control continuity was confirmed. The propeller was separated from the engine and exhibited circumferential scoring around the fracture surface. No anomalies were noted with the engine. An autopsy of the pilot was conducted by the Saginaw County Medical Examiner on December 13, 2002. The FAA's Final Forensic Toxicology Fatal Accident Report of the pilot reported the following: 0.058 (ug/ml, ug/g) diphenhydramine detected in blood diphenhydramine present in urine quinine detected in urine Diphenhydramine (commonly known by the trade name Benadryl) is an over-the-counter antihistamine with sedative affects, most commonly used to treat allergy symptoms, but also indicated for severe nausea and itching. It is present in many over-the-counter multi-symptom preparations. Quinine is found in tonic water, and is used to treat severe malaria. It is also commonly used to reduce the frequency of nocturnal leg cramps (a condition which may cause painful led muscle spasm at night), and is available as an over-the-counter nutritional supplement marketed for this purpose. The FAA does not regulate the use of any specific prescription or over-the-counter medications by pilots, though the Federal Aviation Regulations (FAR) do state that (Sec. 91.17): "No person may act or attempt to act as a crewmember of a civil aircraft ... While using any drug that affects the person's faculties in any way contrary to safety ...." FAA Aviation Medical Examiners are instructed to defer medical certification to the FAA Aeromedical Certification division for any airman undergoing continuous treatment with "sedating antihistaminic" medications, among others.