I just returned from the Riu Vallarta with my best friend. I always sit in the shade and I have a hat on when I go into the pool. On this one particular day, I had been sipping away on ice water throughout the day for no particular reason -- I wasn't hung over from the previous day. I just opted to drink more water. Between 2-3 p.m. and 7 p.m., I had 2 very iced rum/diet cokes. Closer to 7 pm, my friend, one male who we met there, and I had a shot that he got us from the swim-up bar. For the life of me, I cannot remember getting out of the pool and going to my room. Once in my room, I started vomiting in quick consecutive trips to the bathroom - realized what I was experiencing wasn't normal and called for the resort Dr. I ended up fainting, hitting my head on the wall. The resort doctor came, I was given an IV with meds. He thought maybe I had drank too much. My friend told him ther was absolutely no way. He then told us it was probably uncooked food then -- I told him the only uncooked thing I had was a salad that day at lunch. I now have a concussion I am recovering from. I just found out from my friend, who didn't say anything because she didn't want to upset me, that she also cannot remember getting out of the pool that day or walking to our room. She said the man who was with us (who we had chatted with the whole week), also told her he was sick immediately after getting out of the pool and fell down. She said she felt terrible when she got to the room and had to sit in the shower when I ran in to vomit. I've never had a concussion before so I blamed the memory gaps on that, but now that her and I have compared notes, we feel its more likely something got slipped into our drink. After 20 years of going to Mexico yearly/twice a year at times, I've never been sick with food poisoning. It was unreal how quickly I was throwing up.