If Weed Makes You Extremely Nauseated, You're Not Alone

In the fall of 2016, I became an egg donor. Following my hormonal treatments and egg retrieval, I began to experience unusual bouts of nausea. I didn’t think much of it at first, assuming it was an interim experience attributed to the hormonal changes my body was undergoing. I also found that cannabis, which I’d typically used to treat insomnia, provided temporary relief from the sick feeling in my stomach.

But as time went on, the rounds of nausea became prolonged and more severe. The smell and sight of food repelled me. I couldn’t bring myself to eat, sometimes for days on end, and I started to lose a lot of weight. I scheduled an appointment with a gastroenterologist to see if we could figure out what was going on.

I had noticed that the more I used cannabis to treat my nausea, the more sick I felt during the hours I wasn’t smoking. It seemed counterintuitive that cannabis might be playing a role in my sickness since it’s often recommended to alleviate nausea, but I felt compelled to tell the doctor I’d been smoking on a regular basis.

To my surprise, he told me that U.S. states that had legalized the medical or recreational use of cannabis, leading to an increase in cannabis usage, had also seen a significant rise in a condition known as cannabinoid hyperemesis syndrome (CHS). I was consistently experiencing prolonged nausea throughout the day—a common symptom of CHS. Because I smoked cannabis on a regular basis, the doctor believed my condition was, in fact, linked to cannabis use. My various test results came back normal, indicating he was likely right.

CHS is a puzzling condition occurring in long-term cannabis users. Common symptoms include extreme nausea, intractable vomiting, and abdominal pain. Many patients report finding relief by taking hot showers. It’s an unusual illness given that medical cannabis is often used to treat the nausea of cancer patients, for example. But it turns out that while cannabis is frequently effective against nausea and vomiting, it can also trigger it.

The symptoms of CHS sometimes take years to surface. The first course of action for cannabis users suffering from severe nausea and/or uncontrollable vomiting should be to cease cannabis use and see if symptoms subside within 2-3 days. I was advised to do this, and within two days, I was completely back to normal.

The cause of CHS is unknown. Because cannabis has complex chemical properties, it makes it difficult to pinpoint what leads to this seemingly paradoxical syndrome. Some research is focused on the body’s receptors which are affected by cannabis use. Heavy, frequent use is thought to deregulate receptors, causing the symptoms of CHS. Cannabis use, however, has been common for centuries in countries like India, and symptoms of CHS have only begun to be reported in the last couple of decades. In addition, there are no reports of CHS by chronic users in some regions, such as South Asia, at least not to the extent we see in the United States. This has led some doctors to be skeptical of the idea that cannabis itself is the problem, theorizing that additives may be the issue instead. In the case of Asia, however, lack of reports may also be due to the fact that weed remains strictly illegal in many of its largest countries, even as it gains acceptance in the West.

In my case, my fertility specialist believed CHS was directly linked to changes in my receptors caused by the hormones I was taking. I was scheduled to undergo a second round of egg donation, and he thought it was possible my receptors would revert back to normal afterward. Sure enough, following the second procedure, I no longer experienced the symptoms of CHS when using cannabis.

Cannabis use is increasing across the country as states not only legalize its recreational use, but also as it becomes increasingly seen as an effective alternative treatment to many commonly used pharmaceuticals, including opioids. Regardless of its cause, doctors expect to see a rise in cases of CHS coinciding with its increased use. Hospitals across the country have already seen more and more cases of CHS in states where weed has been legalized.

Cannabis was illegal in my state, so I was hesitant to tell the doctor I’d been using it. And, because of my unique situation, it would have been easy to blame my symptoms on recent hormone treatments, especially since cannabis provided temporary relief. But if I hadn’t been transparent, I would have continued to be sick. Be honest with your doctor if you use cannabis regularly and begin to exhibit these symptoms. Also be aware that many doctors may not yet be aware of CHS, and you may need to be the one to bring this possibility to their attention. It likely won’t remain under the radar for long, however. As cannabis continues to become more acceptable and accessible across the United States, we’ll need to work toward developing a better understanding of what causes CHS and how to prevent it.