You know ive been reading all the responses, we've had this discussion many times over here, other forums, on LOBs etc and almost all the responses relate to sea sickness being the cause of puking. Not sure if this is a whole other thread to start or if medical people are reading this thread but I've only gotten seasick once in my life, in a river, with about 45000 nautical miles under my belt - my issue is sudden onset violent migraines that occur midway to the latter part of a dive. I have a bad habit of diving a tiny bit deeper than a lot of other people so I have considered pressure, but theres no correlation between the depth they have come on at, be it 15m or 35m, so ive ruled that out. Im a chronic migraine sufferer and have been all my life, not just underwater, and im not lucky enough to be one of the people who get an aura warning of an impending migraine. On land I have about 25 minutes between feeling that pain in my head and taking medication which stops the progression to puking, underwater there is about 3 - 5 minutes before going..oh no..and puking.
It doesn't overly bother me, DAN said they didn't see migraines as contraindication to diving nor has any doctor ive seen for dive medicals, I just puke my way gradually to the surface and try not to offend any of my fellow divers who ive puked near and then retreated to my cabin to puke and sleep when I can get to my medication. I dont get migraines any more frequently diving and travelling than I do at home so I'd be curious to hear if anyone else has this annoying issue.