Cannabinoid Hyperemesis Syndrome (CHS)

Overview

Cannabinoid hyperemesis syndrome (CHS) is a condition that affects some people who use cannabis regularly and heavily over a long period. It causes repeated episodes of severe nausea, vomiting, and abdominal pain. A striking and characteristic feature is that symptoms are often temporarily relieved by hot showers or baths, which leads many people to bathe compulsively during an attack.

CHS can be confusing because cannabis is sometimes used to ease nausea, yet long-term heavy use can paradoxically cause it. The condition tends to follow a cycle of well periods interrupted by intense bouts of vomiting. The most important point is that CHS resolves with sustained cannabis cessation, and recognizing this can prevent years of repeated illness and unnecessary tests.

Many people with CHS go through repeated emergency visits and extensive testing before the diagnosis is made, partly because the link to cannabis is not always obvious and partly because some people continue to use cannabis to try to relieve their nausea, which only continues the cycle. As cannabis products have become more potent and more widely used, awareness of CHS has grown. Understanding the condition is empowering, because unlike many causes of chronic vomiting, it has a clear and effective remedy: stopping cannabis.

Symptoms

CHS typically follows a pattern with three phases, though presentations vary. Common features include:

• Recurrent bouts of severe nausea and forceful, repeated vomiting
• Abdominal pain, often in the upper abdomen
• Strong urge to take frequent hot showers or baths, which temporarily relieve symptoms
• Relatively well periods between attacks
• Reduced appetite and weight loss during episodes

Severe, prolonged vomiting can lead to dehydration and salt imbalances, which may cause dizziness, weakness, and reduced urination. These warrant urgent care.

Causes

CHS is caused by long-term, frequent cannabis use. The exact mechanism is not fully understood, but it is thought to involve the effects of cannabinoids on the digestive system and the body's temperature and stress-regulating systems after prolonged exposure.

• Chronic heavy cannabis use: Usually daily or near-daily use over months to years before symptoms begin.
• Cumulative exposure: Symptoms often emerge after a long period of regular use rather than after a single occasion.

The relief from hot water is believed to relate to how cannabinoids affect body temperature regulation, though this is not fully explained.

Risk Factors

• Daily or near-daily cannabis use
• Long duration of regular use, often years
• Starting cannabis use at a young age
• High-potency cannabis products

Diagnosis

There is no single test for CHS, so doctors diagnose it from the pattern of symptoms and history, after ruling out other causes of cyclic vomiting. Helpful clues include long-term heavy cannabis use, recurrent vomiting, and relief with hot bathing. Evaluation may include:

• A detailed history of cannabis use and symptom pattern
• Blood tests to check hydration and salt levels
• Tests to exclude other causes, such as imaging or an upper endoscopy
• Confirmation that symptoms resolve when cannabis is stopped

CHS shares many features with cyclic vomiting syndrome, and the two can be hard to tell apart; the strong link to regular cannabis use and the relief from hot bathing are the most useful distinguishing clues. Doctors are careful to rule out other serious causes of repeated vomiting, such as a bowel obstruction, gallbladder disease, or a problem in the brain, before settling on the diagnosis. The most convincing confirmation comes over time: when symptoms clear after stopping cannabis and stay away, the diagnosis is supported, whereas a return of symptoms with renewed use further confirms it.

Treatment & Management

The only lasting cure is to stop using cannabis. Management has two parts.

• Treating an acute attack: Fluids to correct dehydration, anti-sickness medication (standard anti-nausea drugs are often only partly effective), and supportive care. Some specific medications and topical capsaicin cream applied to the abdomen are used in some settings, the latter thought to act on the same heat-related pathways as a hot shower.
• Long-term treatment: Complete and sustained cannabis cessation, which resolves the syndrome. Support to stop, including counseling, is often needed.

During a severe attack, the priority is to replace lost fluids and salts and to control the vomiting enough to keep the person comfortable and safe. Standard anti-nausea medicines are often only partly effective in CHS, which can be frustrating, and this limited response is itself a clue to the diagnosis. The lasting solution lies in stopping cannabis: symptoms usually take several days to a few weeks to settle fully after quitting, and they typically return if cannabis use resumes. Because stopping can be difficult, practical support such as counseling or a cessation program makes success more likely.

Self-Care & Prevention

• Stop using cannabis to prevent recurrence; this is the key step
• Seek support, such as counseling, to help quit if needed
• Stay hydrated during recovery
• Recognize early symptoms so you can act before severe dehydration develops
• Avoid resuming use, as symptoms typically come back

When to See a Doctor

See a doctor if you have recurrent bouts of severe vomiting, especially if you use cannabis regularly and find relief in hot showers. Seek emergency care if you have:

• Vomiting that will not stop or prevents keeping fluids down
• Signs of dehydration such as dizziness, very dark urine, or passing little urine
• Severe abdominal pain
• Vomiting blood or material that looks like coffee grounds

Prolonged vomiting can cause dangerous dehydration and salt imbalances that need prompt treatment.

Related Topics

Frequently Asked Questions

References

1. American College of Gastroenterology. Cyclic Vomiting Syndrome and Cannabinoid Hyperemesis.
2. Mayo Clinic. Cannabinoid hyperemesis syndrome.
3. Substance Abuse and Mental Health Services Administration (SAMHSA).
4. MedlinePlus, U.S. National Library of Medicine.