The THC in weed helps to relieve nausea in a lot of people, but this board and others like it are full of experiences from first-time smokers who smoked and then vomited.

I don't think anyone knows why that happens, but my theory is it's probably the unfamiliar smoke and resultant coughing combined with maybe an overload of all the substances you're inhaling for the initial time mixed with a touch of anxiety. Inhaling any type of irritant can sometimes tickle the back of the throat and provoke the gag reflex. Alcohol is often being ingested, too, and that'll increase the risk of getting sick. My guess is that some or all of these factors just makes new weed smokers sometimes get sick at their stomach.

Fortunately, from what I've read, most of these brave, courageous people haven't let their first-time barfing experience deter them from trying again and successfully becoming non-vomiting smokers. The key seems to be to take it nice and easy until you know how you'll react.