Cannabinoid Hyperemesis Syndrome is said to affect somewhere between 2 and 3 million Americans.

Cannabinoid Hyperemesis Syndrome: When cannabis causes the pain

CHS is a very unpleasant, potentially very dangerous gastrointestinal illness that, some studies have estimated, might plague as many as 12.5 percent of regular cannabis users

“Ellen” grew up in South Berkshire County and when she was 15, took up a daily marijuana habit. “The best thing I had,” she said, “was escaping reality.” In July 2020, now living in a big city, she came down with intense stomach pains and nausea. Alarmed, she went to the ER, where doctors gave her IV fluids, but offered no diagnosis. “No one there knew what was wrong,” she said. “I thought I was gonna die, and no one cared.” She was discharged no closer to understanding what had caused the episode than when she’d come in, and suffered at home, in pain and vomiting, for another two weeks. Eventually a nurse friend told her the name of her problem. Ellen is the one who introduced me CHS, or Cannabinoid Hyperemesis Syndrome.

CHS is a very unpleasant, potentially very dangerous gastrointestinal illness that, some studies have estimated, might plague as many as 12.5 percent of regular cannabis users, or about 2,750,000 Americans. There’s no cure for CHS, and it can take up to several weeks or even months to feel any significant improvement in your health. The only thing to do if you never want to experience it again is to abstain from cannabis.

When it was first identified back in 2004, and as recently as November 2019, CHS was referred to as rare, but Dr. Adam Cohen, director of Emergency Medicine at Southwestern Vermont Medical Center, said, “It wasn’t rare, we just didn’t recognize what it was … The more you look, the more you find it. It’s more ubiquitous than we think.” He wrote an article about the problem in 2020, “Marijuana Related Stomach Disorder On The Rise,” in an effort to raise public awareness.

CHS now accounts for about two in 20 patient visits to Dr. Cohen’s ER. Berkshire Medical Center’s Dr. Michael McHugh, chairman of the Emergency Medicine Department, reckoned that the number of patients presenting with CHS symptoms in his ER is higher. Dr. Sharon Levy, director of Adolescent Substance Use and Addiction at Boston Children’s Hospital, said, “CHS, when I started practicing, was just something you read about. Now I see it every week.” A 2018 study of heavy cannabis users in a large urban hospital found that about one third of them exhibited CHS symptoms. Dr. Joseph Habboushe, who led the study, extrapolated from those numbers that it affects somewhere between 2 and 3 million Americans.

Image courtesy Saint John Emergency Med

People often use marijuana to mitigate pain and stress, but if it is overused, over time, it can paradoxically have the opposite effect. The human body has its own naturally occurring endocannabinoid receptors; “endo” means internal. Marijuana is an exogenous cannabinoid, with “ex” meaning external. CHS occurs when users have fried the body’s endocannabinoid receptors, so they are no longer available to help with physical or emotional pain. As Dr. Cohen explained, “When you start using exogenous sources like marijuana, you end up needing more and more, and then your own endogenous systems don’t cut it anymore … When they stop [using cannabis], they are dealing with those stress and pain problems even worse than before.” Katie Nava, a nurse in Southern California, a recovering CHS sufferer, and an administrator for a CHS Facebook Recovery group, said, “Weed is a like a snake in the grass; it causes what it cures. It takes away my anxiety, then sends it through the roof.”

You can google the number of people who went to the ER for motor vehicle crashes, or for injuries sustained by playing a sport, but precise numbers on CHS are impossible to come by. There are several reasons for this. Abdominal discomfort is the number one reason people see their primary care doctor and seek emergency treatment, and there are many possible causes for it. The problem with CHS, said Dr. McHugh of BMC, is that, “It mimics other things.” The nausea and intense pain associated with CHS — “on par with kidney stones,” said Dr. Cohen — can be mistaken for cyclic vomiting syndrome, acid reflux, gall bladder issues, colitis, or some form of GI cancer, among other possibilities.

But there are some telling hints that point in the direction of CHS, such as the failure to respond to anti-emetic drugs, and finding relief from symptoms by applying scalding hot water. In fact, sufferers often burn themselves by keeping hot water bottles on their bellies all day, or by spending hours under a hot shower. Sean, a frequent CHS sufferer who lives in Maine, told me, “I can’t count the number of times I have boiled myself like a lobster in a bathtub.” He described the feeling of an episode as similar to being filled with gasoline with no way to get it out, like he’s being constantly wrung out like a cloth that never actually gets wrung out. Katie said it felt like knives stabbing into the center of her solar plexus, and then twisting around and around nonstop.

ER visits for CHS also tend to be longer than for other causes, Dr. Cohen said. “They don’t check in, check out an hour or two later. They’re usually slogging it out eight to 10 hours.” After being discharged, CHS patients will often return for continued hydration, or at the onset of another episode. Many sufferers, like Sean and Katie, rack up dozens of ER visits over many years.

Image courtesy Business Insider

Treatments can include anti-anxiety meds and topical capsaicin cream. Improvising and experimenting can also lead to relief, Dr. Cohen has found. “Because you are releasing THC from your fat stores, you are breaking down body fats … we try to shut down that process, mediated by insulin. We give them dextrose. Purely anecdotally, we’ve found this is better than meds alone. I tell people to sip ginger ale as soon as they feel it [an episode] coming on.” Nava said, “I have people take digestive enzymes, because when you eat, you get enzymes from the food that help you digest. If you don’t eat, you don’t get those enzymes. Our [CHS sufferers’] food is not digesting; it just sits in our stomachs and rots.” She also encourages the use of magnesium.

Another difficulty with diagnosis, as Ellen discovered in Boston, is that some doctors still don’t know about CHS, or accept it as a diagnosis. Sufferers might be subjected to all sorts of expensive tests and in-patient treatments, and the reason for their ER visit might then be officially categorized in a hospital’s official data, not as CHS, but under a vague umbrella term.

Dr. Adrian Elliot, head of the Emergency Department at Fairview Hospital, said of CHS, “The diagnosis code is new [October 2020] and cases are being lost in the total number of Nausea/Vomiting coded cases … Additionally, it is difficult to get to the diagnosis of Cannabinoid Hyperemesis Syndrome, as getting all of the history needed to make the definitive link between marijuana use and the nausea/vomiting patient complaint is difficult in the emergency department setting.”

This leads to the third, and perhaps most consequential reason why CHS so often goes undiagnosed. CHS patients are often in a state of denial about the source of their pain. It can take five or six ER visits before they are willing to acknowledge that marijuana could possibly be connected to their physical misery. With the many proven benefits of marijuana taking center stage in this cultural moment, we have been acculturated to believe that marijuana is a pain reliever, not a pain producer, and a cure for nausea, not a cause of nausea. CHS sufferers are therefore extremely resistant to any suggestion that their medicine could be turning against them.

“There is a lot of denial about this,” said Dr. Cohen. “This was one of the obvious things about it. There is always a defensiveness, ‘No, no, no. That can’t be it. We just have to keep looking for the real reason.’” Nava concurred. “It never dawned on me it was weed, because everything I have be preprogrammed to believe was that weed is good for you.”

Dr. Elliot said he tells his skeptical patients to, “Just do an experiment on yourself … Stop for a week, a couple weeks. See if you get better.” This, he said, is a hard sell. “We see young people and adults over and over again.” In fact, users will often increase their marijuana use in response to the CHS-induced nausea, which, of course, only exacerbates it.

Another barrier to correct diagnosis is marijuana’s enduring outlaw status at the federal level, which could lead some patients to withhold the truth of their substance use history from medical professionals. Recreational cannabis is still illegal in 32 states, and is federally categorized, or “scheduled,” alongside heroin and cocaine. Using cannabis, even medicinally, can still get employees fired from certain jobs or students expelled from certain schools. For this same reason, research funding on both the health benefits and health risks of the drug is restricted, so there’s a huge void in our understanding.

The financial costs of CHS are likewise difficult to get a handle on, but they’re extensive. An emergency department gets reimbursed for a single visit, but that does not include the costs incurred to the hospital for the staff hours. “Compared to an ankle sprain, this problem can consume 20 times as much for the hospital,” Dr. Cohen calculated. He sees, on average, two patients presenting with CHS symptoms on each shift.

On a personal level, Sean spends, he estimated, “$100 per episode.” (Pedialite, Gatorade, fruits, soup, etc.) “I’m lucky I have a well, but electricity for heating the water, washing and drying towels … As far as medical bills, I don’t have an exact number, but at upwards of a thousand dollars a visit, with close to 100 visits, with no insurance…”

Nava had excellent health insurance and paid only about $10,000 out of pocket for all her tests and visits over four years of misdiagnosis, with MRIs, CT scans, endoscopies, GI specialists, ER docs, and a specialist who wanted to remove her gall bladder “just in case.” She has a friend with undiagnosed CHS who was given a full hysterectomy in the quest for the root of her problem.

Dr. Erik Messamore, a psychiatrist who’s written and presented about CHS, quotes from a 2012 study that determined the average CHS sufferer has already been suffering from the condition for five years before being diagnosed, has gotten five abdominal CT scans, made 17 ED visits, and been admitted to the hospital seven times, with the average cost of just the ED and hospital admissions being $95,000 per patient.

The Facebook CHS Recovery group now has over 13,000 members, with about 200 joining each week from around the world. It offers virtual support for people at all stages of recovery. Their testimonials speak of the heavy physical, financial, personal, professional, and emotional toll of CHS.

“How long can a person literally go without eating and drinking? We are on day 9 of this nightmare. Constant ER visits for hydration but still can’t tolerate anything in the stomach. Ideas?”

“When I was in the ER for the 5th time because of CHS and still not knowing what was going on there was a heart doctor who was helping out the ER that day, and he was the one who finally asked me if I smoked marijuana and explained this sickness that they were starting to see more and more of due to weed.”

“Just got home from the hospital with my boyfriend … he can’t hold down a job because he’s always sick. I’m fourteen weeks pregnant and I’m afraid I’ll be doing everything on my own because he can’t do anything. He smokes about a gram of oil a day 80% thc or higher and has been for over ten years now.”

“After years in and out of the ER and seeing many specialists, and missing too many life events to count, I haven’t had a single episode since I decided enough was enough. Hang in there everyone, it’s so worth it to quit!”

“I just recently found out what CHS was and I check every box when it comes to symptoms. I had no idea for those 6ish months that weed was doing this to me so of course I kept smoking thinking it was helping.”

“My marriage of 18 years is falling apart! I’ve lost my job because of CHS.”

“I never realized how much control weed had on my life and never knew that it could be such an addiction. I never in a million years would I have known it was physically going to take a toll on my body.”

“Just got out of the hospital for my worst episode in a year. Tried smoking…ended up with double aspiration pneumonia and had to have my heart restarted.”

Administrator Nava points out adamantly that the group is not “anti-weed,” or anti-legalization. They are pro-education. She would like to see the cannabis industry be more proactive in warning buyers about the possibility of CHS. “The dispensaries should have up posters that say, ‘Do you have GI problems you can’t explain? Maybe it’s CHS.’ If they put the warnings up, people would be aware. I would have cut back.”

Sean has cut back on his use but said, as of now, he has no intention of breaking up with his best friend. “I started smoking when I was 13, not long after my grandmother was diagnosed with a terminal illness … Since then, I was in love, and how couldn’t I be? It did nothing but help me, tamed the loudness in my head, allowed me focus, creativity … The only relationship I have had longer than the one I have with marijuana is the one I have with my parents.”

Ellen also decided to reduce her intake rather than quit entirely. Unfortunately, she wound up back in the ER this summer, where the doctor diagnosed her with cyclic vomiting syndrome.

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