Treatment for Cannabinoid Hyperemesis Syndrome (CHS)
Complete and permanent cessation of cannabis use is the only definitive cure for CHS and must be the primary treatment goal. 1, 2
Acute Management in the Emergency Department
First-Line Pharmacologic Interventions
Haloperidol or droperidol should be your first-line antiemetic agents, as butyrophenones reduce hospital length of stay by nearly 50% (6.7 vs 13.9 hours, p=0.014) compared to conventional antiemetics. 2 These dopamine antagonists are consistently more effective than standard antiemetics like ondansetron, which often fails in CHS. 1, 3
Benzodiazepines (particularly lorazepam) are the most effective acute treatment for nausea and vomiting in CHS based on multiple prospective studies, addressing both the stress-mediated component and providing powerful sedation. 2, 4, 5
Topical capsaicin 0.1% cream applied to the abdomen activates TRPV1 receptors and provides consistent symptomatic relief as an adjunctive therapy. 1, 2 This mimics the mechanism of hot showers that patients compulsively use. 1
What NOT to Use
Never use opioids - they worsen nausea, carry high addiction risk, and do not address the underlying pathophysiology. 1, 2, 4 This is a critical pitfall to avoid.
Ondansetron may be tried but expect limited efficacy compared to its use in other conditions, as CHS does not reliably respond to conventional antiemetics. 1, 3
Supportive Care
Provide intravenous fluids for dehydration and correct electrolyte abnormalities. 6, 7 Hot showers or baths provide temporary relief and serve as a diagnostic clue (present in 44-71% of cases). 1, 2
Diagnostic Confirmation Before Treatment
Rule out life-threatening conditions first: acute abdomen, bowel obstruction, mesenteric ischemia, pancreatitis, and myocardial infarction. 1, 2 Once excluded, confirm CHS diagnosis requires all three criteria:
- Cannabis use >1 year before symptom onset with frequency >4 times weekly 1, 2
- Stereotypical episodic vomiting ≥3 episodes annually 1, 2
- Complete symptom resolution after 6+ months of abstinence or duration equal to 3 typical vomiting cycles 1, 2
Long-Term Management and Prevention
Tricyclic antidepressants (amitriptyline) are the mainstay of long-term preventive therapy: start at 25 mg at bedtime and titrate weekly by 25 mg increments to reach the minimal effective dose of 75-100 mg. 1, 2, 4 This is the only medication with evidence for preventing recurrent episodes.
Cannabis cessation counseling is essential and non-negotiable - inform patients that complete resolution requires at least 6 months of continuous abstinence. 1, 2 This is both diagnostic and therapeutic.
Provide psychological support, as anxiety and depression are common comorbidities. 1, 4 Consider co-management with psychiatry for patients with extensive psychiatric comorbidity or treatment resistance. 1
Perioperative Considerations
For patients undergoing surgery, the American Gastroenterological Association and British Journal of Anaesthesia recommend enhanced multimodal antiemetic prophylaxis that differs from standard PONV protocols. 2 Anticipate higher anesthetic and analgesic requirements in chronic cannabis users. 2
Cannabis Withdrawal Syndrome Overlap
Be aware that 47% of regular cannabis users experience withdrawal symptoms (anxiety, irritability, insomnia, GI symptoms) within 24-72 hours of cessation, peaking at days 2-6. 4 This acute withdrawal phase lasts 1-2 weeks. 4 For patients with severe withdrawal consuming high amounts of cannabis, consider referral to addiction medicine specialists who can guide treatment with nabilone or nabiximols substitution. 4
Common Pitfalls
CHS is frequently underdiagnosed due to limited clinician awareness, leading to extensive unnecessary testing. 2, 3 Once CHS is suspected based on cannabis use pattern and hot water bathing behavior, focus on making an early diagnosis rather than pursuing exhaustive investigations. 4 The prevalence continues to rise with increasing cannabis potency and legalization. 3, 6