What happened
Prior to departure, the pilot obtained a weather briefing for a coastal route that had been flown several times previously. During this briefing, the FAA FSS briefer advised against VFR flight due to rain, clouds, and low visibility.
While en route, the pilot contacted the destination airport control tower, reporting a position five miles west of Juneau International Airport. The controller informed the pilot that while the airport remained VFR, weather conditions were lower to the west; the controller also noted that two other aircraft located to the west were unable to land due to the poor weather.
The pilot indicated an intention to attempt arrival from a different direction. Approximately nine minutes later, the pilot radioed that he was "turning around." Shortly after this transmission, the controller heard an ELT signal. The wreckage of the aircraft was recovered on an island approximately three miles south of the destination airport at an elevation of about 5/500 feet MSL. The impact forces destroyed the airplane.
Findings
A postmortem toxicology test performed on the pilot revealed the presence of Dextromethorphan and Chlorpheniramine in both the blood and urine. Chlorpheniramine is a component found in various over-the-counter cold medications and carries warnings against operating machinery due to the risk of drowsiness. Dextromethorphan is commonly used as a cough suppressant.