JUNEAU (AP) -- Over-the-counter drugs might have contributed to a plane crash that killed four Juneau residents last year, federal investigators say.
A doctor outside the investigation, however, says the amount of medicine found was so small it likely didn't play a role.
Private pilot Glenn Cave took a cold medicine that causes drowsiness some time before he crashed his Cessna into a North Douglas mountain ridge in bad weather, according to a final report released by the National Transportation Safety Board. The August 1999 crash killed everyone on board, including Cave's wife Shirley, and newlyweds Jason and Jessica Lidholm.
The NTSB report lists the probable cause as Cave's continued flight into low visibility, clouds and rain without use of flight instruments, and lists factors associated with the accident as ''mountainous/hilly terrain, low ceilings, the pilot's improper in-flight decision making, and the pilot's impairment from over-the-counter drugs,'' the Juneau Empire reported.
Investigators wrote that a postmortem toxicology test revealed the presence of chlorpheniramine and dextromethorphan in Cave's blood and urine. Dextromethorphan is used as a cough suppressant and chlorpheniramine is found in a number of over-the-counter cold remedies, according to the NTSB report.
''The warning associated with (chlorpheniramine) states, in part: Do not drive or operate machinery while taking this medicine as it may cause drowsiness,'' the report said. The NTSB investigator who wrote the report is traveling and could not be reached for comment, but a physician with the Federal Aviation Administration said the amount of chlorpheniramine found in Cave's blood was insignificant.
The exam revealed 0.017 micrograms of the drug per milliliter of blood, according to the report.
''I think it's very, very slight traces. That could have been taken a long time ago. In my opinion it would have no impact at all on his performance,'' said Dr. Robert Rigg, who helps pilots with medical problems as part of his job for the FAA. Rigg emphasized he had not read the NTSB's final crash report. He said the FAA doesn't allow pilots to use any medication that might cause sedation, preferably eight to 12 hours before they fly -- depending on the drug and other factors.
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