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Cannabinoid Hyperemesis Syndrome (CHS) and the Cyclic Vomiting Syndrome (CVS) in Adults
CHS and CVS Overview
- What are cannabinoid hyperemesis syndrome (CHS) and cyclic vomiting syndrome (CVS)?
Both cannabinoid hyperemesis syndrome (CHS) and cyclic vomiting syndrome (CVS) cause people to feel sick to the stomach and throw up repeatedly in “attacks.” Between these attacks, people often feel normal and healthy. The main difference between CHS and CVS is that CHS occurs in people who use marijuana (cannabis) frequently.
Symptoms
- What are the symptoms of cannabinoid hyperemesis syndrome (CHS) and cyclic vomiting syndrome (CVS)?
CHS usually starts after years of using marijuana many times a week. Symptoms of CHS can go away with stopping marijuana use, typically after 6 or more months.
Common triggers for CVS include stress, infections, excitement, not getting enough sleep, and motion sickness.
Symptoms usually cycle through different stages:
- A warning stage, where patients feel sick to their stomachs
- A vomiting stage, where patients throw up a lot, often for hours to days
- A recovery stage, where patients slowly feel better
- A well stage, where patients feel normal until the next attack
Each patient with CHS and CVS experiences slightly different symptoms, particularly in the warning stage. Some common symptoms patients experience in the warning stage include feeling hot or cold, restless, anxious, or sweaty. The warning stage typically lasts for about one hour before the vomiting stage begins.
In the vomiting stage, patients experience a combination of uncontrollable vomiting, retching, gagging, and abdominal pain. The duration of this stage can vary and sometimes can last up to a week. Taking a hot bath or shower may offer relief for some patients. Experts used to think this just happened with CHS, but it is also seen in CVS.
Diagnosis
- What are the symptoms of cannabinoid hyperemesis syndrome (CHS) and cyclic vomiting syndrome (CVS)?
The diagnosis of CHS and CVS is largely based on symptoms. However, many people end up getting blood tests, imaging of their abdomen, and sometimes a procedure before they are diagnosed with CHS or CVS. Often a procedure called an upper endoscopy is used, where a doctor looks at the esophagus, stomach, and part of the small intestine with a camera. Sometimes another test is used to see how quickly or slowly food moves through the stomach. Experts may pursue these other tests to make sure patients do not have other conditions with similar symptoms. Healthcare providers should also review medications and supplements patients are taking, as well as different substance intake, including marijuana and alcohol, as these can all impact symptoms.
Treatment
- What are the symptoms of cannabinoid hyperemesis syndrome (CHS) and cyclic vomiting syndrome (CVS)?
It is important to get regular sleep and manage stress. The most effective way to make CHS better is to stop using marijuana. Some patients who have more frequent symptoms are given medications to prevent attacks and to make the vomiting stage less severe.
Call your doctor or get help right away if you:
- Cannot keep any fluids down
- Feel very dizzy or weak
- Pee much less than normal
- Have chest pain or trouble breathing
Author(s) and Publication Date(s)
Ryan T. Hoff, DO, PeaceHealth Gastroenterology, Vancouver, WA and Claire S. Faulkner, MD, MPH, Boston Medical Center, Boston, MA - Updated August 2026.