Narrative:

While at cruise pilot not flying reported extreme uncomfortable feeling of doom and lack of sufficient oxygen and; with an abundance of caution; asked pilot flying to land at the nearest suitable airport. While pilot not flying donned an oxygen mask; pilot flying declared emergency and we were vectored to a nearby airport. During the descent pilot not flying reported feeling somewhat better and subsequently removed the mask. Upon landing we were met by medical personnel who transported pilot not flying to the local hospital for evaluation. Other than severe diarrhea; all test results were normal and pilot not flying was released to return home. Cause of anomaly was inconclusive however severe diarrhea lasted all weekend. Suspected cause was intestinal virus.

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Original NASA ASRS Text

Title: Hawker 800 Captain reports becoming ill in flight and requesting the First Officer divert for medical attention. This sudden illness occurred at FL400 during a ferry flight.

Narrative: While at cruise pilot not flying reported extreme uncomfortable feeling of doom and lack of sufficient oxygen and; with an abundance of caution; asked pilot flying to land at the nearest suitable airport. While pilot not flying donned an oxygen mask; pilot flying declared emergency and we were vectored to a nearby airport. During the descent pilot not flying reported feeling somewhat better and subsequently removed the mask. Upon landing we were met by medical personnel who transported pilot not flying to the local hospital for evaluation. Other than severe diarrhea; all test results were normal and pilot not flying was released to return home. Cause of anomaly was inconclusive however severe diarrhea lasted all weekend. Suspected cause was intestinal virus.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.