Marijuana: A user’s guide to the good, the bad and the ugly
Part 3: The Ugly
By: Katherine Hill
Edited By: Namrata Damle
Note: This is Part 3 in a three-part series. Click here for Part 1 (the good) and here for Part 2 (the bad).
Thirty years ago marijuana was the boogeyman of polite society. Nancy Reagan and parents across the United States warned children to “Just Say No.” Since then, marijuana’s image has undergone a remarkable rehabilitation. Today many Americans consider marijuana relatively benign at worst, or at best a possible cure for everything from cancer to epilepsy.
The whiplash in public opinion and deluge of conflicting media coverage has understandably left many people with more questions than answers when it comes to marijuana: Is it safe? Should I use it? Will it help my anxiety? Will it cause me to vomit uncontrollably for hours or days at a time?
Unfortunately, because marijuana is one of the most strictly regulated drugs in the country, very little high-quality research has been performed on most claims related to pot, be they good or bad. Research is likely to increase now that both laws and public opinion are beginning to thaw, but it will be years before results from any large studies will be available.
For those of you who have plans for the next weekend rather than the next decade, this three part series will answer these questions and others by taking an unbiased look at what current scientific evidence says about the good, the bad and the just plain ugly of marijuana use.
The Ugly
This third and final part of the series focuses exclusively on Cannabinoid Hyperemesis Syndrome (CHS), which when it comes to possible marijuana side effects, is about as ugly as it comes.
CHS is a subtype of a particularly fun ailment called Cyclic Vomiting Syndrome. Cyclic Vomiting Syndrome (CVS) is more or less exactly what it sounds like. Sufferers experience intense episodes of uncontrollable vomiting, often accompanied by nausea and extreme abdominal pain. Vomiting episodes can last for anywhere from several hours to a full week. After they recover, patients feel fine for several weeks or months before the whole thing starts all over again.
While experiencing these episodes, patients often bathe or shower compulsively in hot water. Hot water seems to relieve some of the symptoms, but no one is exactly sure why. When patients show up in the emergency room, physicians generally treat them with medications to calm the patient and reduce the amount of acid in the stomach, both of which seem to help end episodes more quickly.
CVS has no known cause, basically by definition. It is a kind of a catch-all term for mysterious uncontrollable vomiting, so if physicians can determine what caused a vomiting episode, the patient is given a more specific diagnosis. The syndrome’s intense symptoms and unclear cause have perplexed physicians for years. CVS’s rarity has made it even more difficult to study, and most of the existing research on the disease consists of case reports that follow only a handful of patients each.
CVS’s rarity may also partially explain why it was only within the last two decades that physicians began to notice that a large percentage of CVS patients, possibly as high as 50%, were also chronic marijuana smokers. Even after physicians began to connect the two, it was not immediately clear that marijuana was causing CVS. Quite the opposite, marijuana is known to have anti-nausea effects. It could be that patients with CVS were likely to use marijuana because they were self-medicating to control the symptoms of their condition.
In 2004, a small South Australian study of chronic cannabis users found that nine patients (out of 19) stopped experiencing CVS symptoms after they quit using cannabis. Three of the nine patients later attempted to resume marijuana use. All three redeveloped CVS.
Based on the South Australian study and a small body of similar evidence that was trickling out of research hospitals including Mayo Clinic, experts recommended the creation of a new subtype of CVS called Cannibinoid Hyperemesis Syndrome (CHS). CHS is difficult to distinguish from classic CVS. Its only distinguishing features are that 1) patients develop the disease after chronic marijuana use and 2) patients stop experiencing symptoms after they stop using the drug.
It may seem strange that marijuana, which is known for its ability to curb nausea symptoms, could cause episodes of uncontrollable vomiting, what is known as a “paradoxical effect.” Paradoxical effects occur when the drug has one effect at a low dose, and the opposite effect at a higher dose. One of the best-known paradoxical effects comes from marijuana itself: users often experience relaxation at a low dose but the opposite (paranoia) at a high dose.
So how likely are you to get CHS from using cannabis? Not very. First, scientists still are not 100% sure that cannabis can cause CHS. Although the evidence definitely points in that direction, research is still too thin to establish a definitive link
Second, the people who develop CHS tend to be extremely heavy smokers, on the order of several joints a day for a decade or more. If you are someone who uses marijuana socially at the occasional party, then you probably do not have that much to worry about. If you are someone who has smoked daily for over a decade, then you should probably be more worried, although mostly for reasons other than CHS.
Finally and most importantly, CHS is extremely rare. Even if you are a heavy marijuana user, your likelihood of developing the syndrome is low. However, low is not the same as nonexistent.There is evidence that the incidence of CHS is increasing as marijuana use becomes more common. In Colorado, the number of yearly emergency room visits due to CHS almost doubled after the legalization of cannabis from 41 visits out of 113,262 visits total to 87 visits out of 125,095.
87 cases still isn’t much to write home about, and no one is pegging CHS as the next great public health crisis or anything. Still, if you’re a frequent marijuana user and you find yourself vomiting uncontrollably for days on end, it probably wouldn’t hurt to explore some alternate hobbies.
Sources
Allen, J. H., De Moore, G. M., Heddle, R., & Twartz, J. (2004). Cannabinoid hyperemesis: cyclical hyperemesis in association with chronic cannabis abuse. Gut, 53(11), 1566–1570.
Blumentrath, C. G., Dohrmann, B., & Ewald, N. (2017). Cannabinoid hyperemesis and the cyclic vomiting syndrome in adults: recognition, diagnosis, acute and long-term treatment. GMS German Medical Science, 15.
Heaney, K. (2017, August 30). Will Smoking Pot Make Me Vomit Forever? The Atlantic. Retrieved from https://www.theatlantic.com/health/archive/2017/08/cyclic-vomiting-syndrome/538398/
Pattathan, M. B., Hejazi, R. A., & McCallum, R. W. (2012). Association of marijuana use and cyclic vomiting syndrome. Pharmaceuticals, 5(7), 719–726.
