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Cannabis PlantCannabinoid Hyperemesis Syndrome (CHS)

What is CHS and what causes it?

CHS is a condition that may affect people who use cannabis. Research on CHS is limited and the causes of CHS are not fully understood. However, some studies suggest that using cannabis often and over a long period of time may increase the risk of developing CHS.

What are the symptoms of CHS?

CHS may cause symptoms such as repeated nausea and vomiting. People with CHS may also experience abdominal pain after using cannabis. Some research suggests that CHS can be divided into three phases:

  1. Pre-emetic (or Prodromal) Phase: In this phase, a person may experience early morning nausea, a fear of vomiting (without actually vomiting), and abdominal pain. This phase can last for months or years.

  2. CHS May Cause Nausea

    Hyperemetic Phase: In this phase, a person may experience intense and ongoing nausea, repeated vomiting, abdominal pain, decreased food intake, weight loss, and dehydration. Symptoms of dehydration may include dizziness, dark urine or less frequent urination, extreme thirst, sudden confusion, and unexplained sleepiness or tiredness. This phase can last 24-48 hours and may continue until the person stops using cannabis.

  3. Recovery Phase: In this phase, which can last for days, weeks, or months, a person may feel relatively well. However, symptoms may return if cannabis use is continued.

How common is CHS?

The likeliness of developing CHS is unclear. CHS is a newly identified condition. People may have CHS and not seek medical attention. Those that seek medical attention may be misdiagnosed by a health care provider.

It is unclear why some people who use cannabis often and for a long period of time develop CHS and others don't and if genetics play a role.

When should I call my health care provider?

If you are experiencing symptoms of CHS, contact your health care provider. If your symptoms are severe or you think you need immediate medical attention, call 911 right away.

How is CHS diagnosed?

There is no medical test that confirms a diagnosis of CHS. A health care provider may diagnose CHS based on reported symptoms, medical history, and by ruling out other causes of nausea and vomiting. The only way to confirm a CHS diagnosis is if symptoms are resolved after stopping cannabis use. Some people with CHS may not be diagnosed for several years or may be misdiagnosed. CHS is often confused with Cyclical Vomiting Syndrome because the symptoms experienced are similar.

How is CHS treated?

The only known way to cure CHS is to stop using cannabis products. Some research suggests that CHS is typically resistant to antiemetic drugs (medications for treating nausea and vomiting).  

Some people experiencing CHS reported that their symptoms were relieved by hot baths or showers. However, taking too many hot baths or showers may increase dehydration. A health care provider may recommend additional treatments to relieve CHS symptoms.

How is CHS prevented?

Not using cannabis in any form is the only way to prevent CHS. Stopping cannabis use can also lead to other health benefits.


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