What is Cannabinoid Hyperemesis Syndrome?
Cannabinoid Hyperemesis Syndrome (CHS) is a rare condition that causes repeated and severe bouts of vomiting in people who use cannabis over an extended period. It’s not known why some people develop CHS and others don’t, but it occurs most often in people who use cannabis daily over a period of many years.
Even the direct cause of CHS is unknown, although researchers speculate it has something to do with the THC receptors in the gut. Unlike THC receptors in the brain which quell nausea and reduce vomiting, cannabinoids in the gut can sometimes have the opposite effect, increasing nausea. Over time, it’s believed that these receptors lose their effectiveness and nausea and vomiting increase but at this point, they’re really not sure.
There are three phases of CHS, the prodromal phase, the hyperemetic phase, and the recovery phase. During the prodromal phase, morning nausea is common as well as belly pain. Some people use cannabis more in an effort to reduce the nausea and may develop a fear of vomiting. This phase can last months or even years. Often symptoms come in bouts, with periods of feeling fine in between.
In the hyperemetic phase, nausea and vomiting are at their most intense. Sufferers may become dehydrated and lose interest in food and drink resulting in weight loss. Many people find relief from the symptoms through very hot showers which impacts the hypothalamus, which is responsible for regulating both our body’s temperature and nausea. This phase may last until the person completely stops using cannabis.
Once someone with CHS stops using cannabis, they begin the recovery period and will feel better until cannabis is reintroduced into their system.
Unfortunately, CHS is hardly the only condition that can use nausea, belly pain and vomiting, so it’s important not to diagnose yourself. Your doctor will perform a variety of tests to rule out severe health problems. Since CHS is relatively new, your doctor may not be familiar with it. If you think you may have CHS, educate yourself beforehand and bring some supporting information for your doctor, just in case.