CHS and CVS Overview

Both cannabinoid hyperemesis syndrome (CHS) and cyclic vomiting syndrome (CVS) cause people to feel sick to the stomach and throw up at times, while feeling normal at other times. When you feel sick, you can also have pain in the belly. This is more common in men than women and usually starts around 35 years old. These two conditions are hard to distinguish between and the main difference is CHS happens with using a lot of marijuana.

Cannabinoid Hyperemesis Syndrome (CHS)

CHS usually starts after years of using marijuana many times a week. Initial symptoms are feeling sick to the stomach, belly pain and the feeling like you may throw up. A lot of people can still eat without throwing up. After about 10-12 years of chronic marijuana use, patients begin to have a strong feeling of sickness, throwing up, and belly pain. This is normally when people go see a doctor to find out what is causing these problems. They start to feel better when they stop using marijuana but can feel bad if they use it again.

Cyclic Vomiting Syndrome (CVS)

Patients with CVS also have times where they are feeling sick to the stomach and can also throw up for between 12 hours to about a week. This can happen when you are stressed, excited, have an infection or when women have their period.

Clinical Features, Diagnosis and Treatment

Because we do not know a lot about these two problems, your regular doctor may not think about them as a cause of your sickness. This can make it take a long time to figure out what is happening, and it can take around 10 years from the time you start having trouble.

Important symptoms include:

  • Feel sick to the stomach and throw up at times, while feeling normal in between
  • A little increase in body temperature
  • Headache
  • Loose bowels/diarrhea

These usually happen for 3 to 4 days but can last as long as 1 week in bad cases. You can feel normal when not having the problem.

The pain is usually around the belly button and can get better with hot shower/baths. Some patients use hot water bags across the center of their belly and can burn the skin if done a lot.

When people are sick, they can also sweat and just not feel right. The throwing up can be bad and can cause you to be low on body water. We fix this by giving the water back through the veins and giving drugs to stop the sick feeling and lower the acid in the stomach.


Most people end up having an abdominal ultrasound, upper scope, and a test to see how fast stuff gets out of the stomach before we figure out that their problem is CVS or CHS. We do these to make sure that nothing really bad is happening.

  • Abdominal ultrasound is a very easy test and is done while you are awake. It does not hurt and is fast to do.
  • Upper scope takes about 15-20 minutes. We give you medicine to help you sleep during the test, so you do not know what exactly goes on during it.
  • The stomach emptying test can take a few hours to do. You do not have to be put to sleep for this. It takes longer than normal to get stuff out of the stomach in CHS. Stuff can be getting out of the stomach too fast in CVS.

So we can figure out if you have CVS or CHS, we look for the below differences.

Most important:

  1. Feeling sick to the stomach and throw up at times with pain in the belly
  2. Feeling normal at other times
  3. Tests do not find anything else causing these problems.

Also important:

  1. Losing more than 10 pounds
  2. Being younger than 50 years old
  3. Being able to eat normally when not sick
  4. Belly pain that gets better with hot water bags across the belly, hot showers or hot baths

The most important thing to make CHS better is stopping marijuana use. Your doctor probably should send you to see a stomach doctor, who knows more about your problem and can help you feel better.