Narrative:

On route from ZZZ1 to ZZZ2 the captain suddenly felt sick and threw up. He went to the forward lavatory and got sick once more. When he returned he said he was feeling better and would be able to continue the flight to ZZZ2. Approximately 5-10 minutes later his symptoms returned and he threw up again. At this point; we decided to divert the flight to ZZZ. An emergency was declared with both dispatch and ATC as a precaution and the flight proceeded without further incident as I made the approach and landing and the captain performed all the pilot not flying duties.

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Original NASA ASRS Text

Title: B757 Captain becomes very ill during first hour of cross country flight. Crew elects to divert so that Captain can seek medical attention.

Narrative: On route from ZZZ1 to ZZZ2 the Captain suddenly felt sick and threw up. He went to the forward lavatory and got sick once more. When he returned he said he was feeling better and would be able to continue the flight to ZZZ2. Approximately 5-10 minutes later his symptoms returned and he threw up again. At this point; we decided to divert the flight to ZZZ. An emergency was declared with both Dispatch and ATC as a precaution and the flight proceeded without further incident as I made the approach and landing and the Captain performed all the Pilot Not Flying duties.

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.