Cannabinoid Hyperemesis Syndrome (CHS): Symptoms and Treatment

Nausea and vomiting accompanied by stomach cramping or pain is a common set of symptoms present in many conditions, including the stomach flu and food poisoning. However, cyclical vomiting syndrome (CVS) or psychogenic vomiting, repeated episodes of severe nausea and vomiting without any indication of infection or illness, is not. CVS is more common in children than adults, and it is sometimes associated with behavioral problems. Some research suggests that it may be a variant of migraine headache or abdominal migraine.^1,2

In 2004, doctors in South Australia first described episodes of cyclical vomiting of unknown origin in adult patients who were regular marijuana users.³ Additional case reports and research on the condition, cannabinoid hyperemesis syndrome (CHS), continue to be published and CHS is still not fully understood nearly 20 years later. Thus, the condition may go unrecognized and undiagnosed as a result.³

Therefore, the prevalence of CHS is difficult to gauge though one study out of Colorado found that after the legalization of cannabis, emergency room visits for CVS increased.^2,4 A separate study evaluating people who had a history of smoking cannabis 20 days or more per month found that approximately one-third exhibited the symptoms of CHS.⁵ Consequently, marijuana was also the most prevalent federally illicit drug used in 2020—with more than 49 million individuals reporting past-year marijuana use.⁶

What Is Cannabinoid Hyperemesis Syndrome (CHS)?

CHS is a rare condition associated with long-term, regular (daily or weekly) cannabis use that’s characterized by severe nausea, vomiting, and stomach pain that run in cycles.⁷ Individuals with CHS commonly find relief from frequent or long-lasting hot showers.⁷

Symptoms of Cannabinoid Hyperemesis Syndrome

Symptoms of CHS and their severity depend on the phase of the syndrome. Common symptoms of CHS may include:⁷

• Morning sickness.
• A fear of throwing up.
• Intense abdominal discomfort or pain.
• Persistent nausea.
• Repeated vomiting and retching (i.e., making the sound and movement of vomiting).
• Loss of appetite.
• Weight loss.

Those with CHS may also feel compelled to take hot showers or baths. This may be due to the soothing effects of hotter temperatures, which temporarily alleviate the symptoms.⁷

CHS Phases and Timeline

It can take years of cannabis use to develop CHS. A 2011 report published in Current Drug Abuse Reviews noted that “in nearly all cases, there is a delay of several years” from the time marijuana smoking started to when the first CHS symptoms are experienced.⁸

Research suggests there are 3 phases of CHS, including:⁷

1. The prodromal phase. Individuals experience general morning sickness and abdominal discomfort or pain during this phase. Since these symptoms are relatively mild and can occur after years of cannabis use, many people continue to smoke marijuana or even increase their consumption due to the belief that cannabis will settle their stomachs. Thus, this phase can last for months or years.
2. The hyperemetic phase. This is the acute phase of CHS. During this phase, CHS’ effects intensify. Individuals experience intense and persistent nausea and vomiting. There is typically a persistent mild abdominal pain as well. Due to the severity of the symptoms, individuals may struggle with weight loss and dehydration.
3. The recovery phase. Individuals get to this phase when they abstain from cannabinoid use and symptoms begin to fade. However, if a patient starts using cannabis again, symptoms tend to recur.

What Are the Possible Complications of CHS?

Frequent vomiting can lead to complications, including:^9,10

• Dehydration and electrolyte imbalances, which can result in nutritional deficiencies and renal failure.
• Aspiration, which can result in inflammation of lung tissue (pneumonitis) and aspiration pneumonia (when vomit is breathed into the lungs or airway).
• Esophagus rupture and other esophageal injury such as tears in the tissue.
• Low potassium (hypokalemia).
• Low levels of phosphorous in the blood (hypophosphatemia).
• Air trapped in the chest cavity between the lungs (pneumomediastium).

What Might Cause CHS?

Researchers have several theories on the causes of CHS—none of which is strongly supported by evidence. Some of these theories include:^3,7

• Genetics. Some individuals might be more susceptible to cannabis toxicity due to genetic variations.
• Dysregulation of certain receptors. Researchers identified two receptors—CB1 and CB2 located in the brain, gastrointestinal tract, nervous system, and immune system—to which marijuana binds. These receptors respond to specific stimuli or changes in the environment. CB1 receptors, specifically, regulate the effects of marijuana on the gastrointestinal tract. In the short term, marijuana can help decrease nausea and vomiting by activating these CB1 receptors. However, chronic stimulation of these receptors might decrease their activity, leading to CHS.
• Slowed digestion. Stimulation of these receptors in the gut may slow digestion enough to cause nausea and vomiting.
• Toxic buildup. Long-term marijuana use might lead to an accumulation of cannabinoid components in the brain and fatty tissues of the body that cause a toxic effect.
• Enlarged blood vessels. Marijuana may cause an increased dilation of blood vessels in the gastrointestinal tract, leading to CHS.
• A stress response. Long-term marijuana use might dysregulate the hypothalamic-pituitary-adrenal axis, which is a physiological arm of the stress response, leading the CHS symptoms.
• Disruption of temperature control. Cannabis might disrupt the body’s ability to regulate temperature, which could contribute to symptoms, especially those temporarily alleviated by hot showers and bathing.

Risk Factors for Developing Cannabinoid Hyperemesis Syndrome

Not every person who uses marijuana—even long term—develops CHS. While it is certain that individuals who use marijuana frequently (on a daily or weekly basis for at least a year) or in prolonged high doses are at an increased risk of getting CHS, not much is understood beyond that. Additional evidence is needed to better understand or identify factors that may contribute to an individual’s overall risk of developing CHS, including the potency of marijuana, co-occurring physical or mental health conditions, ethnicity, or socioeconomic environmental factors.⁷

How Is CHS Diagnosed?

For a number of reasons, CHS is often missed as a diagnosis. Individuals with CHS may not disclose their drug use or they may not seek medical care. It’s an emerging diagnosis that may be overlooked in the emergency department, where many individuals go to seek help.⁷

In order to be diagnosed with CHS, certain criteria must be present, including:^7,11

• Long-term, frequent marijuana use—at least more than 1 year.
• Severe cyclic vomiting episodes after prolonged, high-dose cannabis use.
• Stabbing abdominal pain.
• Symptoms stop when the individual sustains abstinence from marijuana use.
• May be associated with compulsive bathing in hot water.

To further complicate the diagnosis, CHS bears a strong resemblance to another condition called cyclic vomiting syndrome (CVS).¹² While CVS presents the same way, the triggers that cause CVS are different, including lack of sleep, stress, certain foods, but not marijuana.²

Tips for Dealing with CHS Symptoms

It’s well documented that individuals with CHS find temporary relief by taking hot showers or baths. One case study found capsaicin—the chemical found in chili peppers that makes your mouth burn—in a cream form eased painful abdominal pain for an individual with CHS.¹³ In some cases, anti-anxiety medication helped provide relief for individuals with CHS.¹⁴ However, the only sustainable solution to resolve CHS symptoms is to stop marijuana use.¹⁴

Cannabinoid Hyperemesis Syndrome Treatment & Outlook

While there is no standard for treating CHS, there are options to treat the symptoms, but all of them lack robust research pointing to their effectiveness. For instance, some research suggests that benzodiazepines—specifically lorazepam—showed a positive response in the treatment of CHS.¹⁵ Other studies indicate that the antipsychotic medication haloperidol, given intravenously to individuals with CHS, has been effective in symptom relief.¹⁵ However, after alleviating the symptoms associated with CHS with medications and/or creams, treatment includes patient education and counseling to help the individual stop their marijuana use since research suggests that’s the most likely way to resolve CHS in most patients.¹⁴ In fact, one study found about 84% of the patients who received treatment for CHS reported abstinence from marijuana use. Of those, more than 86% reported resolution of their CHS symptoms.¹⁵

If you or a loved one have a marijuana use disorder and struggle to quit, professional treatment can help. While research is virtually nonexistent on the efficacy of addiction treatment for individuals with CHS, drug rehab treatment for marijuana use can help you achieve lasting abstinence, which studies suggest may likely resolve the symptoms associated with CHS.

Find Marijuana Addiction Treatment Near You

If you are worried about your marijuana use, it’s time to reach out for help. Treatment for marijuana use is available. We can help you find the marijuana addiction program that fits your needs and begin your recovery journey today. Call us today at to learn about your treatment options and to take the first step onto the road to recovery.

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