Cannabinoid Hyperemesis Syndrome
What is cannabinoid hyperemesis syndrome?
Cannabinoid hyperemesis syndrome
(CHS) is a condition that leads to repeated and severe bouts of vomiting. It is rare and
only occurs in daily long-term users of marijuana.
Marijuana has several active
substances. These include THC and related chemicals. These substances bind to molecules
found in the brain. That causes the drug “high” and other effects that users feel.
Your digestive tract also has a
number of molecules that bind to THC and related substances. So marijuana also affects
the digestive tract. For example, the drug can change the time it takes the stomach to
empty. It also affects the esophageal sphincter. That’s the tight band of muscle that
opens and closes to let food from the esophagus into the stomach. Long-term marijuana
use can change the way the affected molecules respond and lead to the symptoms of
Marijuana is the most widely used
illegal drug in the U.S. Young adults are the most frequent users. A small number of
these people develop CHS. It often only happens in people who have regularly used
marijuana for several years. Often CHS affects those who use the drug at least once a
What causes cannabinoid hyperemesis syndrome?
Marijuana has very complex effects on the body. Experts are still trying to learn exactly how it causes CHS in some people.
In the brain, marijuana often has the opposite effect of CHS. It helps prevent nausea and vomiting. The drug is also good at stopping such symptoms in people having chemotherapy.
But in the digestive tract,
marijuana seems to have the opposite effect. It actually makes you more likely to have
nausea and vomiting. With the first use of marijuana, the signals from the brain may be
more important. That may lead to anti-nausea effects at first. But with repeated use of
marijuana, certain receptors in the brain may stop responding to the drug in the same
way. That may cause the repeated bouts of vomiting found in people with CHS.
It still isn’t clear why some heavy
marijuana users get the syndrome, but others don't.
What are the symptoms of cannabinoid hyperemesis syndrome?
People with CHS suffer from
repeated bouts of vomiting. In between these episodes are times without any symptoms.
Healthcare providers often divide these symptoms into 3 stages: the prodromal phase, the
hyperemetic phase, and the recovery phase.
Prodromal phase. During this phase, the main symptoms are often early morning
nausea and belly (abdominal) pain. Some people also develop a fear of vomiting. Most
people keep normal eating patterns during this time. Some people use more marijuana
because they think it will help stop the nausea. This phase may last for months or
Hyperemetic phase. Symptoms during this time may include:
Repeated episodes of vomiting
Decreased food intake and weight
Symptoms of fluid loss
During this phase, vomiting is
often intense and overwhelming. Many people take a lot of hot showers during the day.
They find that doing so eases their nausea. (That may be because of how the hot
temperature affects a part of the brain called the hypothalamus. This part of the brain
effects both temperature regulation and vomiting.) People often first seek medical care
during this phase.
The hyperemetic phase may continue
until the person completely stops using marijuana. Then the recovery phrase starts.
Recovery phase. During this time, symptoms go away. Normal eating is possible
again. This phase can last days or months. Symptoms often come back if the person tries
How is cannabinoid hyperemesis syndrome diagnosed?
Many health problems can cause
repeated vomiting. To make a diagnosis, your healthcare provider will ask you about your
symptoms and your past health. He or she will also do a physical exam, including an exam
of your belly.
Your healthcare provider may also
need more tests to rule out other causes of the vomiting. That’s especially the case for
ones that may signal a health emergency. Based on your other symptoms, these tests might
Blood tests for anemia and
Tests for electrolytes
Tests for pancreas and liver enzymes,
to check these organs
Urine analysis, to test for infection
or other urinary causes
Drug screen, to test for drug-related
causes of vomiting
X-rays of the belly, to check for
things such as a blockage
Upper endoscopy, to view the stomach
and esophagus for possible causes of vomiting
Head CT scan, if a nervous system
cause of vomiting seems likely
Abdominal CT scan, to check for health
problems that might need surgery
CHS was only recently discovered.
So some healthcare providers may not know about it. As a result, they may not spot it
for many years. They often confuse CHS with cyclical vomiting disorder. That is a health
problem that causes similar symptoms. A specialist trained in diseases of the digestive
tract (gastroenterologist) might make the diagnosis.
You may have CHS if you have all of these:
Long-term weekly and daily marijuana use
Severe, repeated nausea and vomiting
You feel better after taking a hot shower
There is no single test that confirms this diagnosis. Only
improvement after quitting marijuana confirms the diagnosis.
How is cannabinoid hyperemesis syndrome treated?
If you have had severe vomiting,
you might need to stay in the hospital for a short time. During the hyperemesis phase,
you might need these treatments:
IV (intravenous) fluid replacement for
Medicines to help decrease
Proton-pump inhibitors, to treat
Frequent hot showers
In a small sample of people with CHS, rubbing capsaicin cream on
the belly helped decrease pain and nausea. The chemicals in the cream have the same
effect as a hot shower
Symptoms often ease after a day or
2 unless marijuana is used before this time.
To fully get better, you need to
stop using marijuana all together. Some people may get help from drug rehab programs to
help them quit. Cognitive behavioral therapy or family therapy can also help. If you
stop using marijuana, your symptoms should not come back.
What are possible complications of cannabinoid hyperemesis
Very severe, prolonged vomiting may lead to dehydration. It may also lead to electrolyte problems in your blood. If untreated, these can cause rare complications such as:
Muscle spasms or weakness
Heart rhythm abnormalities
In very rare cases, brain swelling (cerebral edema)
Your healthcare team will quickly work to fix any dehydration or electrolyte problems. Doing so can help prevent these problems.
What can I do to prevent cannabinoid hyperemesis syndrome?
You can prevent CHS by not using
marijuana in any form. You may not want to believe that marijuana may be the underlying
cause of your symptoms. That may be because you have used it for many years without
having any problems. The syndrome may take several years to develop. The drug may help
prevent nausea in new users who don’t use it often. But people with CHS need to
completely stop using it. If they don’t, their symptoms will likely come back.
Quitting marijuana may lead to
other health benefits, such as:
When should I call my healthcare provider?
Call your healthcare provider if you have had severe vomiting for a day or more.
Key points about cannabinoid hyperemesis syndrome
CHS is a condition that leads to
repeated and severe bouts of vomiting. It results from long-term use of
Most people self-treat using hot
showers to help reduce their symptoms.
Some people with CHS may not be
diagnosed for several years. Admitting to your healthcare provider that you use
marijuana daily can speed up the diagnosis.
You might need to stay in the hospital
to treat dehydration from CHS.
Symptoms start to go away within a day
or 2 after stopping marijuana use.
Symptoms almost always come back if you use marijuana
Tips to help you get the most from a visit to your healthcare provider:
Know the reason for your visit and what you want to happen.
Before your visit, write down questions you want answered.
Bring someone with you to help you ask questions and remember what your provider tells you.
At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
Ask if your condition can be treated in other ways.
Know why a test or procedure is recommended and what the results could mean.
Know what to expect if you do not take the medicine or have the test or procedure.
If you have a follow-up appointment, write down the date, time, and purpose for that visit.
Know how you can contact your provider if you have questions.
Online Medical Reviewer:
Eric Perez MD
Online Medical Reviewer:
Marianne Fraser MSN RN
Online Medical Reviewer:
Raymond Kent Turley BSN MSN RN
Date Last Reviewed:
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