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Medically reviewed by Danesh Alam MD, DFAPA, DFASAM
Cannabis hyperemesis syndrome (CHS) is a condition in which long-term, frequent cannabis use causes repeated bouts of severe nausea, vomiting, and belly pain. Many people find that hot showers ease the symptoms for a while. Usual anti-nausea medicines often help little. The only lasting cure is to stop using cannabis completely.
Go to an emergency room if you cannot keep fluids down, have signs of dehydration such as dizziness, confusion, or very little urine, or see blood or dark, coffee-colored material in your vomit.
What is cannabis hyperemesis syndrome?
NIDA defines CHS as nausea, vomiting, and abdominal pain "after long-term, heavy cannabis use." NIDA: Cannabis (marijuana) The CDC adds that episodes start suddenly and can be "severe and debilitating." CDC MMWR: CHS emergency department visits It is also called cannabinoid hyperemesis syndrome. In the popular press it is sometimes nicknamed "scromiting," short for screaming and vomiting. Clinical and Experimental Emergency Medicine: CHS in the emergency department
CHS can seem like a contradiction: cannabis can ease nausea at low doses but cause vomiting at higher doses. Pharmaceuticals: Review of cannabis hyperemesis syndrome Many people keep using it during early symptoms, expecting it to help.
What are the symptoms of CHS?
The main symptoms are episodes of intense nausea, vomiting, and belly pain, with weeks or months of feeling well in between. Researchers describe three phases. Pharmaceuticals: Review of cannabis hyperemesis syndrome
- Prodromal phase. This early phase can last for months. It brings morning nausea, stomach discomfort, or a fear of vomiting.
- Hyperemetic phase. This phase lasts several days, and symptoms build within hours. Some people vomit or retch up to five times an hour. A racing heart, sweating, hot flashes, and trembling are common.
- Recovery phase. Eating returns to normal and symptoms go away. This can last weeks to months, but going back to cannabis can set off another episode.
The pain can be severe enough that people often have scans to rule out gallstones or pancreatitis before anyone names the cause.
Why do hot showers help with cannabis hyperemesis syndrome?
Hot showers or baths can bring short-term relief, so many people with CHS take long, repeated ones. NIDA notes that people "sometimes try to temporarily relieve their symptoms by taking hot showers or baths." NIDA: Cannabis (marijuana)
No one knows exactly why. One theory is that heat steadies the brain's temperature control, which heavy cannabis use may disrupt. Another involves TRPV1, a heat-sensing receptor that hot water switches on. Pharmaceuticals: Review of cannabis hyperemesis syndrome
Hot showers are a clue, not a test: more than 10% of people with CHS do not take them, and some people with cyclic vomiting syndrome do. Pharmaceuticals: Review of cannabis hyperemesis syndrome
What causes CHS?
The exact cause is unknown. Proposed explanations include changes to the brain's cannabinoid receptors, altered TRPV1 signaling, and disrupted temperature control in the hypothalamus. JAMA Network Open: CHS in US emergency departments, 2016 to 2022
Risk goes up with use for more than six months, daily or near-daily use, and high-potency products such as vapes. Blaming contaminants or a general stomach illness is "not supported by scientific evidence." JAMA Network Open: CHS in US emergency departments, 2016 to 2022
How common is cannabis hyperemesis syndrome?
CHS is a growing reason for emergency visits. In US emergency departments, the CHS rate rose from 4.4 per 100,000 visits in 2016 to a peak of 33.1 in spring 2020. It was still 22.3 in 2022. Adults ages 18 to 25 had the highest risk. JAMA Network Open: CHS in US emergency departments, 2016 to 2022
In Ontario, Canada, monthly emergency visits for CHS rose 13-fold between January 2014 and June 2021, and nearly 1 in 10 visits led to a hospital stay. The sharpest jump came when the legal market expanded with new products and more stores. Legalization alone was not linked to a rise. JAMA Network Open: CHS visits in Ontario
Is there an ICD-10 code for cannabis hyperemesis syndrome?
Yes. Since October 1, 2025, US clinicians can record CHS with ICD-10-CM code R11.16, "Cannabis hyperemesis syndrome." CMS: ICD-10 codes and FY 2026 addenda Before that, CHS had to be pieced together from a vomiting code plus a cannabis code.
The CDC counted 199,565 emergency visits involving CHS from January 2023 through May 2026. In the eight months after the code arrived, CHS visits made up 3.7 times their earlier share of all emergency visits. The CDC says this jump may partly reflect better recognition and coding, not only more cases. People ages 15 to 24 had the highest rates. CDC MMWR: CHS emergency department visits
How is CHS diagnosed?
No single test confirms CHS. Doctors diagnose it from the pattern of symptoms and cannabis use, after ruling out other causes. The Rome IV criteria, used worldwide for gut-brain disorders, require all three: Rome Foundation: Rome IV criteria
- Repeated vomiting episodes that look like cyclic vomiting syndrome in how they start, how long they last, and how often they happen
- Symptoms that begin after long-term cannabis use
- Relief from vomiting episodes after cannabis use has stopped for a sustained period
Long hot baths or showers support the diagnosis but are not required. The 2026 update, Rome V, adds numbers: use for at least a year, on at least four days a week, and relief that lasts at least six months, or three typical cycles, after stopping. Rome Foundation: Rome V criteria The American Gastroenterological Association uses similar thresholds. AGA: CHS clinical practice update
Be honest about cannabis use. The CDC encourages clinicians to ask how often and how long someone uses it, and in what form. CDC MMWR: CHS emergency department visits
What is the difference between CHS and cyclic vomiting syndrome?
The episodes can look the same. The difference is cannabis. CHS starts after long-term, frequent use and goes away once someone stays off cannabis. Cyclic vomiting syndrome is not tied to cannabis, and it often comes with a personal or family history of migraines. Rome Foundation: Rome IV criteria
People with CHS are frequently misdiagnosed with cyclic vomiting syndrome. From 2016 to 2022, emergency visits for cyclic vomiting without cannabis fell while CHS visits rose. JAMA Network Open: CHS in US emergency departments, 2016 to 2022
How is cannabis hyperemesis syndrome treated?
Stopping cannabis completely is the only cure. In NIDA's words, "CHS only resolves when a person stops using cannabis completely." NIDA: Cannabis (marijuana) Treating an episode eases symptoms but does not prevent the next one.
In the emergency room, the first goals are IV fluids and correcting electrolytes such as potassium. Pharmaceuticals: Review of cannabis hyperemesis syndrome Standard anti-nausea drugs often do not work well for CHS. Addiction: CHS review Other options include: AJHP: Managing CHS in the emergency department
- Haloperidol. In a small randomized trial, it worked better than ondansetron, a common anti-nausea drug, and patients left the ER sooner. Annals of Emergency Medicine: Haloperidol vs. ondansetron for CHS
- Capsaicin cream. Made from chili peppers, it is rubbed on the belly and creates a feeling of heat. A review of seven small studies found it appears to help, but larger trials are needed. American Journal of Emergency Medicine: Capsaicin for CHS
The same 2025 review advises against opioids and benzodiazepines as first treatment. AJHP: Managing CHS in the emergency department For people with frequent episodes, a doctor may prescribe a daily medicine to help prevent them. It works less well if cannabis use continues. At home, sipping fluids that contain sugar and electrolytes between episodes can help prevent dehydration. Pharmaceuticals: Review of cannabis hyperemesis syndrome
Is CHS dangerous?
It can be. Hours of vomiting can cause dehydration, low potassium and phosphate levels, and acute kidney injury. Forceful vomiting can tear the lining of the esophagus and bring up blood. Pharmaceuticals: Review of cannabis hyperemesis syndrome Deaths are rare, but they have happened. CDC MMWR: CHS emergency department visits
Get medical care right away, at an emergency room if needed, if you:
- See blood or dark, coffee-colored material in your vomit
- Have not been able to keep any fluids down for 12 hours or more
- Have not urinated for 8 hours or more
- Have been vomiting for longer than 24 hours
MedlinePlus: Nausea and vomiting in adults Call 911 if someone faints, becomes confused, or has a seizure. MedlinePlus: Dehydration
Why is it hard to stop using cannabis?
Quitting is often harder than it sounds. NIDA estimates that 22% to 30% of people who use cannabis have cannabis use disorder, a pattern of use that causes real problems or distress. NIDA: Cannabis (marijuana) Our guide to whether marijuana is addictive walks through the signs.
Withdrawal adds to the pull, even for people without a use disorder. Symptoms include irritability, anxiety, restlessness, trouble sleeping, poor appetite, headaches, sweating, and abdominal pain. NIDA: Cannabis (marijuana) Because some of these overlap with CHS, the first weeks off cannabis can be confusing.
Potency matters too. THC strength in seized cannabis rose from about 4% in 1995 to about 16% in 2022, and some dispensary flower and concentrates top 40%. NIDA: Cannabis (marijuana) Higher THC content also raises the risk of psychosis. Deutsches Ärzteblatt International: Cannabis-related emergencies We cover that risk in marijuana-induced psychosis.
No medication is FDA-approved for cannabis use disorder or withdrawal. Behavioral therapies can be effective, including cognitive behavioral therapy, motivational enhancement therapy, and contingency management. NIDA: Cannabis (marijuana) For practical first steps, see our guide to stopping weed.
What if I use medical marijuana in Florida?
The diagnostic criteria for CHS depend on how long and how often someone uses cannabis. They do not depend on why someone uses it or where they buy it. Rome Foundation: Rome V criteria
If you have a Florida medical marijuana card and keep having vomiting episodes, tell the physician who certified you and your primary care doctor. They can help you weigh other options.
Frequently asked questions
What is scromiting?
"Scromiting" is a popular-press nickname for cannabis hyperemesis syndrome, from "screaming" and "vomiting."
How long does cannabis hyperemesis syndrome last?
An episode of heavy vomiting usually lasts several days. Episodes tend to return as long as cannabis use continues. Confirming that stopping has worked can take six months, or about three typical cycles.
Do hot showers cure CHS?
No. Hot showers can bring short-term relief, but the symptoms come back. Only stopping cannabis ends CHS.
Can I keep using a little cannabis if I have CHS?
The evidence points to stopping completely. NIDA says CHS resolves only when a person stops using cannabis completely, and preventive medicine works less well when use continues.
Getting help at Ambrosia
Vomiting episodes need medical care first. If the hard part is stopping cannabis, Ambrosia's marijuana addiction treatment includes inpatient care in West Palm Beach and an intensive outpatient program.
Our weed detox program provides medically supervised care. It begins with an assessment of physical health, substance use, and any co-occurring conditions, and it plans the next stage of treatment. When anxiety, depression, or another condition is part of the picture, dual diagnosis treatment addresses both at once.
For free, confidential treatment referrals at any hour, call SAMHSA's National Helpline at 1-800-662-4357, in English or Spanish. SAMHSA: National Helpline