A 7 year old thread here but this just happened to me this past weekend. Fainted 3 times at about 4:00 in the afternoon when I had just shared a joint and went from sitting to standing...head rush, told my bud I was gonna pass out and hit the ground, was out for maybe 5 seconds. I came to and I was a little shaken but I had no pain, no tingles, felt fine laying there under trees staring at beautiful sky with clouds and leaves...but tried to stand, now he was holding me up...I said "here it comes again" and he helped place me back on the ground. Again, out for a couple of seconds. Layed there for a few more minutes tried to get up again...out again...I would say all in all about 30 minutes of laying in the front yard. Then got up slow, made it to the couch, watched a movie - felt fine. I had eaten very little on Friday and a salad with chicken Saturday noonish with a large ice tea (unsweetend). I have lost a ton of weight lately, my diet is very scant. My guess? It is the dehydrated and low blood pressure scenario. I agree with Jellybean. So, monitor yourselves - eat and drink up if you know you've got a smoke session coming. Google up orthostatic hypotension. Matches my experience to the tee.