Cannabinoid hyperemesis syndrome (CHS) is a condition that causes repeated and severe vomiting and nausea. It usually occurs in people who use marijuana heavily and regularly over many years.
Cannabinoid hyperemesis syndrome is caused by heavy, long-term use of marijuana or cannabis. The condition is rare and little known, even by medical professionals. But as the legalization of marijuana spreads across the United States, CHS is likely to become more common.
Key points about Cannabinoid Hyperemesis Syndrome
- Cannabinoid hyperemesis syndrome causes severe vomiting from long-term, heavy marijuana use.
- Frequent, hot bathing/showers provide temporary symptom relief.
- Stopping marijuana use often resolves CHS vomiting long term.
- Support for quitting and avoiding relapse may be needed with long term heavy use.
- Education can raise awareness of CHS among health providers and cannabis users.
Cannabinoid Hyperemesis Syndrome (CHS) symptoms
The most common symptom of cannabinoid hyperemesis syndrome is cyclic vomiting. This means someone with CHS experiences bouts or episodes of severe nausea and vomiting, followed by periods of no symptoms. These episodes can last for hours or days. Most people with the condition have symptoms monthly, though cycles can happen as rarely as every few months or as often as weekly.
In addition to vomiting, symptoms of CHS can include:
- Extreme nausea
- Abdominal pain
- Weight loss from frequent vomiting
Some people also experience a marked increase in showering or bathing because of recurring feelings of being too hot. Hot showers or baths may relieve nausea temporarily. This temporarily reduces nausea. Doctors call this “compulsive bathing behavior.”
Other possible signs and symptoms of CHS include:
- Intense abdominal pain
- Fear of vomiting
- Panic attacks
The vomiting and nausea from CHS comes in cycles. Most people have an episode, recover fully, and feel well for weeks or months before the nausea and vomiting return. Over time, cycles seem to happen more frequently. They also become more severe and last longer.
Cannabinoid Hyperemesis Syndrome causes
What causes cannabinoid hyperemesis syndrome? The exact cause isn’t known. But it’s strongly linked to ongoing, heavy use of marijuana. Researchers suspect that toxic substances from THC and other components build up in the body over years of heavy cannabis use. These toxins eventually cause the hyperemesis cyclic vomiting episodes.
Several things support the link between heavy, long-term marijuana use and cannabinoid hyperemesis syndrome:
- Most people who develop CHS have used marijuana heavily for 2 years or more.
- CHS was first discovered in South Australia in 2004, a time when high-THC potency marijuana appeared and became more widely available.
- Stopping cannabis use seems to be the only reliable way to resolve CHS cycles long term.
While marijuana use seems a clear trigger, it’s not understood why only some heavy users get CHS. Genetics may make some people more susceptible. One study found CHS patients were more likely to have a history of anxiety, depression, or non-marijuana related nausea and vomiting. But more research is needed on risk factors.
Cannabinoid Hyperemesis Syndrome vs. Cyclic Vomiting Syndrome
Cyclic vomiting syndrome (CVS) has signs and symptoms similar to CHS. With CVS, people have sudden, repeated attacks of severe nausea and vomiting. But there is no link to marijuana use seen with cyclic vomiting syndrome.
It’s not understood exactly how or if CHS and CVS are connected. Some researchers see CHS as a version of CVS triggered by heavy cannabis use. Others suggest they are two distinct conditions. One theory is that CVS patients use marijuana to treat their cyclic nausea, and this later unmasks CHS.
Both CHS and CVS are still being studied. More research on how they are alike and different will help improve diagnosis and treatment.
Cannabinoid Hyperemesis Syndrome diagnosis
There are no blood tests or imaging scans to diagnose CHS. Doctors diagnose it based on symptoms, history of marijuana use, ruling out other causes, and response when cannabis use stops.
Diagnosing cannabinoid hyperemesis can be challenging. Many people with CHS use marijuana to ease nausea and vomiting between episodes. So they don’t think to mention cannabis use to doctors. And many health providers are not yet aware of CHS.
A doctor will consider CHS if someone has:
- Long-term, regular marijuana use
- Repeated bouts of severe vomiting relieved temporarily by bathing
- Abdominal pain, nausea, dehydration
- Symptom cycles over months or years
Other vomiting causes must be ruled out, like:
- Cyclic vomiting syndrome
- Gastrointestinal disorders
- Medication side effects
- Metabolic disturbances
- Brain conditions
Your medical history can help determine if you may have cannabinoid hyperemesis syndrome. Be prepared to give information about:
- How much marijuana you use and how often
- What form you use — smoked, vaped, edible
- When you started using marijuana regularly
- Use of hot showers for symptom relief
- Previous episodes of nausea and vomiting
Lab tests, imaging, and endoscopy of your stomach and intestines may be done to rule out other problems. These test results are normal in people with CHS.
Some studies show that stopping marijuana use gradually resolves symptoms for nearly all CHS patients. If other likely causes are ruled out, improvement after abstaining from cannabis helps confirm the CHS diagnosis.
Cannabinoid Hyperemesis Syndrome treatment
The primary treatment for cannabinoid hyperemesis syndrome is stopping marijuana use completely. This alone often stops symptoms long term without other treatment. But it can take days, weeks, or months for cannabinoid toxins to clear the body fully.
Other CHS treatments focus on relieving current symptoms and preventing complications:
- IV fluids and electrolytes for dehydration
- Antinausea and vomiting meds
- Pain relievers
- Sedatives for anxiety
Hot showers or baths can provide short term relief from CHS nausea and vomiting. But compulsive hot water bathing can cause other problems like dehydration, falls, and skin damage.
In severe cases, hospitalization may be needed for IV hydration, medication, and monitoring. This is especially true if nausea prevents eating or drinking for several days.
Healthcare providers may recommend counseling, support groups, and an addiction treatment program. These can help you stop marijuana use and avoid relapse after months or years of heavy use. Learning new coping methods may also help prevent return to regular cannabis use.
Outlook for Cannabinoid Hyperemesis Syndrome
With treatment, most people with cannabinoid hyperemesis syndrome recover completely after stopping marijuana use. Cycles of nausea and vomiting can return if cannabis use resumes.
Relapsing, heavy marijuana use makes the long-term outlook worse. Repeated episodes seem to increase risk for long term vomiting, nutritional problems, and cognitive issues. Continuing to smoke or vape marijuana can also increase risks for lung diseases, mental disorders, and other substance abuse.
Can CHS be prevented?
The only certain way to prevent cannabinoid hyperemesis syndrome is to avoid marijuana use, or limit use to occasional, small doses.
But for consistent, heavy cannabis users, avoiding CHS may not be simple. Many heavy users develop dependence and experience withdrawal symptoms when stopping marijuana. Withdrawal signs like nausea, anxiety, insomnia, and sweating can also drive restarting use.
People who develop CHS are often unaware of risks from heavy marijuana use over years. Education can help raise awareness of CHS among cannabis users and health professionals. Reducing stigma around cannabis addiction may also help more people get needed treatment.
In states legalizing recreational marijuana, including warnings on labels has been recommended. Customer education in dispensaries on long term heavy use risks could also help. Until more research is done, frequent marijuana users should watch for common CHS symptoms like cyclic vomiting.
Cannabinoid hyperemesis syndrome is an emerging health problem linked to heavy, longtime marijuana use. In states legalizing marijuana, CHS will likely become more common and recognized. Routine screening for cannabis use and education on CHS are important for the public and medical field.
For people with symptoms of cyclic vomiting, nausea, and frequent hot bathing, CHS should be considered. Evaluation of marijuana use history, tests to rule out other causes, and any symptom relief after stopping cannabis use help diagnosis. Complete abstinence from marijuana along with symptom treatment and hydration are essential to recover from cannabinoid hyperemesis syndrome long term.