Despite cannabis being approved by the FDA for nausea and vomiting in cancer patients, some users actually get intense nausea and vomiting from cannabis. When this occurs chronically and for prolonged periods, it is called Cannabinoid Hyperemesis Syndrome, or CHS. The number of patients reporting to emergency departments with this seemingly paradoxical condition has been increasing in states which have legalized cannabis. Although generally not life threatening, this can cause brief hospitalization, costing the health care system and creating disturbances in people’s lives, many of whom are medical patients. If persistent and untreated, it can lead to more complicated issues such as weight loss and kidney failure. So, in today’s article we will look at what CHS is, what scientists think causes it, and how you can avoid getting it or treat it.
What is Cannabinoid Hyperemesis Syndrome?
Cannabinoid hyperemesis syndrome (CHS) is characterized by cyclic nausea, vomiting, abdominal pain, and compulsive warm bathing behaviors. This is most often presented in chronic, long-time cannabis users. This condition was first described less than two decades ago, in 2004 from a case in Australia. Since being described, many more patient’s that had suffered from this condition for many years without any answers have been diagnosed with CHS.
There is no quantitative test for CHS, nor can a person be screened for it. The diagnoses only come after multiple clinical evaluations where no other reason can be given to the cyclic symptoms other than daily cannabis use. According to most studies and case reports, CHS patients all starting using cannabis daily while still in their teenage years. Other risk factors have yet to be identified, but are thought to include amount of cannabis used each day, the method of use, as well as “other confounding medical, psychiatric, ethnic, and socioeconomic conditions.” Essentially, the data is still quite inconclusive, and many more studies are needed.
Who is at risk for CHS?
Since it was first described in 2004, published reports of CHS from around the world have slowly been tricking in. It is unknown at this time exactly how many of the actual cases are covered in these reports, as the description of the syndrome is so new that some doctors and healthcare practitioners would be unfamiliar with the signs and symptoms. However, in a review from 2011 the authors looked into the details of 31 of these publications. According to their data, the vast majority of CHS sufferers were men, at 77%. Most began using cannabis daily as a teenager (average age of 15.9 years). Almost all used cannabis multiple times per day, and for most the symptoms of CHS did not appear until about a decade of daily use (average of 10.2 years).
Most of the sufferers in those studies had experienced CHS for several years without a diagnosis. During presentation to the healthcare facilities, many where given invasive or exploratory procedures including CT scans, colonoscopies, X-rays, and ultrasounds. Those tests cost money and time, and of course yielded no conclusive results. This leaves sufferers of this syndrome in a state of despair, with an average time from first onset to diagnoses being about 4.5 years.
This condition has also been reported in users of synthetic cannabis. In a very interesting case study, a 30-year-old male had used cannabis multiple times daily since 13 years of age. He was experienced cyclical nausea and had presented multiple time to emergency departments, been subjected to hundreds of tests, and found nothing. He then switched to synthetic cannabis because of drug testing at work, and the CHS returned despite him testing negative for THC metabolites at the hospital.
How can I know if I have Cannabinoid Hyperemesis Syndrome?
Cannabinoid Hyperemesis Syndrome has now been described to include 3 phases, which patients generally move through in order. The first phase is called the prodromal phase. This is when patients start to develop mild nausea, particularly in the mornings. It also usually includes some abdominal pain, and a feeling of wanting to vomit. At this stage, patients usually continue eating a normal diet, and often increase cannabis consumption as they believe it will help them feel less nauseas. This stage generally lasts a few months or years.
The next stage of CHS is called the hyperemetic phase. As the name implies, this is the stage in which cyclic and intensely persistent nausea and vomiting are experienced. Patients describe this stage as “overwhelming and incapacitating.” At this stage, many patients will decrease their food intake, or avoid certain foods that they feel are triggers for vomiting. People in this phase face chronic dehydration, weightless, and electrolyte imbalances. Many find some relief by taking a hot bath, so this becomes learned behavior to adapt to the condition, and is thus why it is included in the diagnostic guidelines for the syndrome. Other than being physically and mentally worn down, this is also the stage at which many patients report repeatedly to emergency departments and incur large financial burdens, generally with no clear answers as to what is wrong with them.
The last phase is, of course, the recovery phase, which can last anywhere from a few days to several months. During this time, the patients are abstaining from cannabis use, and thus do not experience any symptoms. However, if they use cannabis than the symptoms will reoccur.
What are the risk factors of CHS and how it is treated?
As mentioned above, researchers still have very little idea about what causes Cannabinoid Hyperemesis Syndrome, or who is prone to get it. But they are working on this, and there are some theories. The first theory involves a genetic factor which leaves some people with less of the enzymes in their body that break down cannabinoids like THC. The second, is based on the fact that THC is lipophilic, or fat soluble. This theory implies that in daily users THC accumulates in the fat of the brain’s cerebellum, eventually achieving emesis levels. The third theory is a bt more complex, but involves the abundance and distribution of CB1 receptors between the central and peripheral nervous systems. The fourth is that long term cannabis use disturbs the hypothalamic-pituitary-adrenal axis. And lastly, that heavy daily cannabis use can affect the hypothalamus, which is largely responsible for regulating homeostatic in the body, and causing the vomiting and explaining the hot bathing.
So, there is really nothing in that list of theories that would indicate to you whether or not you at risk for this syndrome. But luckily this syndrome is incredibly rare, and most users have little to worry about. However, if you or someone you know does experience CHS, what should you do to help them?
What is the treatment of CHS?
Currently, there is no prescribed treatment for CHS, and this article is not a supplement for proper medical care. But, doctors around the country have been making headway based on sharing of case reports of experiences with patients. Of course, these are largely just ways to treat the symptoms until the cannabis can be eliminated from the body through natural processes. So, upon presentation to the emergency department, the first step will be to provide fluids and electrolytes through an IV. If treating at home, you can give beverages with electrolytes to replenish hydration, but only if the person can keep them down, if not, get them to a center where they can receive an IV.
For the pain, acetaminophen and morphine are generally given. At home, this will mean giving a product such as Tylenol, again, only if the patient can keep it down. For the nausea and vomiting, reports often gave benzodiazepines such as lorazepam (Ativan). Lastly, for hiccups some case studies reported improvements after administering the anti-psychotic medication Chlorpromazine.
In a more recent, retroactive study topical capsaicin, the molecule that give chilies their spice, was investigated as a treatment for CHS. Forty-three patients presenting to the emergency department where given topical capsaicin, and although their length of stay in the ED was not significantly reduced, it did reduce the amount of opioids they were given, and 42% had not returned to the ED in the following three months.
Regardless of the efficacy of all these treatments, they are all only ways to control the symptoms until the body can clear the cannabinoids. So, in any case, refraining from consuming cannabis is a requirement to long-term relief.
There is little reason for normal cannabis users to worry about getting CHS. The aim of this article is not to scare anyone, or to provide fuel to the debate against cannabis legalization. As with all my articles, this is an investigation into the science of cannabis, and also a form of harm reduction. Currently there is still a lack of understanding about Cannabinoid Hyperemesis Syndrome, and so please stay tuned to our page as we will bring you updates into this and many other aspects of developments in cannabis science.