I kinda had a mini stroke once, but that was because I was holding hits in for 3 minutes. I heard a strange tone in my head, I got violently nauseous, and threw my guts out. I called my dealer to see if I got some with paraquat or something. My speech was slurred. He said, "No. I would've charged you more!" Ha ha... I then laid down as still as possible, with the room spinning for another 3 hours until it finally went away. I'm sure I'm fine, now...