Just as our most fervent defender of pot posted the most scientifically offensive clause in the legalization initiative defeated by California voters:
5. Cannabis has fewer harmful effects than either alcohol or cigarettes, which are both legal for adult consumption. Cannabis is not physically addictive, does not have long term toxic effects on the body, and does not cause its consumers to become violent.[DM- policy statement, false, false, distraction]
a comment on an older post returned our attention to the cannabis hyperemesis syndrome.
The past year I started smoking a lot more than ever before.
I'm 21, and every single morning I wake up with the worst upset stomach. It gets all the way to the point where I'm running to the bathroom to throw up and nothing ever comes out. The doctors think its in my head. Awesome. When this first began happening I would just make myself throw up but once I began it wouldn't stop for hours and I had to be taken to the emergency room. I feel like I'm dying!! But of course I feel completely better when I go smoke. It's insane!
So I trotted over to PubMed to see what is new, if anything, with cannabis hyperemesis. I found three new CaseReport publications that I had not seen before including:
Nicolson SE, Denysenko L, Mulcare JL, Vito JP, Chabon B. Cannabinoid hyperemesis syndrome: a case series and review of previous reports. Psychosomatics. 2012 May;53(3):212-9. Epub 2012 Apr 4. PubMed
Luther V, Yap L.A hot bath to calm what ails you: the Cannabis Hyperemesis Syndrome. Acute Med. 2012;11(1):23-4. PubMed
Bagdure S, Smalligan RD, Sharifi H, Khandheria B. Waning effect of compulsive bathing in cannabinoid hyperemesis.Am J Addict. 2012 Mar-Apr;21(2):184-5. doi: 10.1111/j.1521-0391.2011.00209.x. Epub 2012 Feb 7. PubMed
There are a total of 6 individuals reported (20-27 yrs of age, 2 female), all of whom presented to medical services (New York, 4; London, 1; Amarillo, TX, 1) with repeated and severe vomiting. All Cases had been smoking marijuana for many years with at least daily smoking in recent months to years. Five of the cases identify multiple uses per day, the sixth just indicates daily smoking.
Medical workups for all six indicated no other detectable gastrointestinal causes. All six Cases include multiple episodes of repeated vomiting in the past which had resulted in emergency department visits or hospitalizations for that patient.
All six had been using hot showers to control their symptoms, selected quotes from different Cases are illustrative:
he persistently demanded to use our showering facilities...He continued to demand to use the showering facilities, and oddly seemed more settled after bathing.
Several times during the interview, he went to the bathroom to put his head under the hot shower, which he said improved his
Ms. B complained that the hospital showers were not warm enough because the best way to relieve her symptoms was to take extremely hot, hour-long showers four times daily.
Three of the cases have evidence that ceasing marijuana smoking prevented further episodes of cyclical vomiting. Three show evidence that returning to marijuana smoking after abstinence led to recurrence of symptoms. Two cases had no followup evidence.
As this evidence starts to accumulate, we need to remember one thing about the Case Reports which is that there is a severe publication/selection bias in this sort of thing. Physicians' motivations to publish are not like ours and what strikes one group of physicians to bother to publish a Report is entirely opaque to me. It is, however, likely only the tip of the iceberg. As a second caution, it may also be the case that their is a bias for the publication of "clean" Cases. For only bothering when the individual Case seems to fit this growing profile to a T. Thus, it may make things about this syndrome appear more clear cut, more severe, etc. This goes both ways but one thing I would be concerned about are those Cases that are indeed caused by chronic cannabis use but are not diagnosed because they don't seem to fit the Case Report literature.
Perhaps hot bathing/showers are not always involved? Perhaps the use history is not as severe as it was for this most recent set of six cases? Perhaps there are some cases in which marginal gastro-intestinal concerns have interacted with a lesser degree of chronic cannabis smoking to push an individual over the threshold to cyclic vomiting symptoms?
There is always the unknown factor. People have proposed unknown toxins in the past...contamination of the cannabis being used. Still not impossible, especially given the apparent rarity of the syndrome. But, I would argue, as the cases occur across time and geography this becomes less likely. You would think that contamination might surround particular drug supplies (in time and space) in a way that might turn up as a geographic patient cluster.
For now, however, the evidence is reasonably strong and it is most certainly growing. Obviously, I think it is well past time for scientists with models that are relevant to emesis to get cranking and start up some studies. Unfortunately rats don't vomit so it is going to require some specialized animal models, perhaps the ferret.