I have had cannabinoid hyperemesis and can't be around any pot. Here's a long personal experience for those of your curious enough to read so much
I smoked it a few times as a teen without ANY issues. I got a script for it in 2006 (I would have been 21) for chronic back pain. For the first 6 months, no problems. At the start I smoked it a few times a week when I was in a lot of pain (I had a spinal fusions/back surgery--was not on any medications or supplements at the time). Maybe around the 2nd or 3rd month on it I was smoking it 1-2x a day (I went through 1g in around a week and a half). For the first 6 months of use I had absolutely no issues with vomiting or nausea.
Right around the 6 month mark, I went away for a weekend. It was the first time for at least a month or so that I did not have any pot for over 24 hours. I started to feel nauseous and I threw up a few hours after. It was the most intense nausea I've ever had. I went to the hospital around 6 hours after I started to vomit. I was throwing up buckets of BILE (the green stuff your liver or whatever it is produces) for a full week, in the hospital because I could not hold anything down. I threw up once every 5minutes to 2 hours or so despite the meds.
I had tons of tests done. All the GI stuff, tons of daily blood work, xrays/scans/MRIs of my body and brain... WORST WEEK OF MY LIFE. They were pumping me full of all the anti nauseas, high and combined doses with zero relief. Showers were the only thing that worked. The nurses thought I was crazy because I kept demanding they let me shower that it made me feel 95% better for 20-30 minutes--they only let me 2-3x a day if that. I should add--the most effective was hot water on my head (laying in the hot bath with my legs out was the best--I didnt over heat but my head stayed hot!). I even tried putting a heat pad "contraption" I made, on my head but it was not hot enough I guess. Plus, the nurses took it away when they realized what I was doing
After around a week in the hospital, I was back to normal (disgustingly thin and weak, though) and was allowed to go home. It was like someone flipped the switch to off. There was no diagnosis made, but my physician had "the" Australian article on this "pot sickness" (as I call it) and she was sure that's what caused my troubles.
I did not want to resort to pain meds for my back (had tried the alternatives...) and so I did research, asked other doctors and, pot gurus (including the docs who prescribe it) and none of them could "agree" the pot had causes my trouble... I had only been using it for 6 months! I began smoking it again, once a week for 2 months to make sure I was fine. Again, no problems. I finally got back up to once a day--I was sure the sickness was a fluke. I started to feel very sick again by the 4th month but the pot made the nausea go away--I smoked it before eating. I was smoking 3-4x a day for a few weeks and decided I wanted to just stop completely because I was then convinced it was indeed the pot. I went through the same vomiting thing for a full week--I spent 4 of those days in the hospital.
I have stayed away from smoking it, but I ended up in the hospital (2x for IVs) 2 months later when I went to a friend's house who smoked it while I was in the room (I did not get a buzz or inhale smoke). And, to this day if I go into a house or area that has recently had pot smoked I end up having bad waves of nausea for 4-7 days (not to the point that I cannot eat, etc) starting pretty much the following day.
Sorry that is so long, but I felt a personal story of this horrible "syndrome" might be beneficial... My observations/understanding is basically, I get sick when the pot is coming out of my system. It did not have anything to do with the pot being good/bad, contaminated, etc... I also tried using a vaporizer in case it was not the THC but something the smoke was causing. Pot is not supposed to give withdrawals but I suspect this is a withdrawal type thing. The first post made a lot of sense to me...
One more thing I would like to add. I am a female, I have never been a drinker and never used drugs, etc... Back pain is from a bilateral fracture that I had surgical fused--no health issues outside of that. I partly think I was so "sensitive" to this thing is because I am very light (105lbs before onset of puking--I ride racehorses, I'm just small) so maybe the THC bonded more to my brain receptors than stored up in any fat... 1 week is around the time it takes for it to clear out of my system on drug tests too. Oh, and I was not eating a ton from munchies--my normal diet.
I still promote the use of this very fine and useful drug. I keep searching for an "answer" in hopes of finding some cure for this syndrome. I still suffer from pain, so it would be so nice to be able to use it again.
If anyone has questions about it, I'm happy to share! I really want people to know about this, maybe there are others and, maybe there is a way to prevent this. Again, sorry it was long