Treatment for Cannabis Hyperemesis Syndrome
Definitive Treatment
Complete and permanent cessation of cannabis use is the only definitive cure for cannabis hyperemesis syndrome and must be the primary therapeutic goal. 1, 2 Symptoms resolve after abstinence for at least 6 months or a duration equal to 3 typical vomiting cycles. 1, 2
Acute Management in the Emergency Department
First-Line Pharmacologic Therapy
Haloperidol or droperidol should be prioritized as first-line agents because butyrophenones reduce hospital length of stay by nearly 50% (6.7 vs 13.9 hours, p=0.014) compared to other antiemetics. 3 These dopamine antagonists demonstrate superior efficacy over conventional antiemetics in multiple case series. 1, 4
Adjunctive Acute Therapies
Topical capsaicin 0.1% cream applied to the abdomen activates transient receptor potential vanilloid type 1 (TRPV1) receptors and provides symptom relief when other treatments fail. 1, 2, 5 All 13 patients in one case series experienced symptom improvement after capsaicin application. 5
Benzodiazepines (particularly lorazepam) are effective for acute management through sedating and anxiolytic effects that address the stress-mediated component of CHS. 3, 4 These were the most frequently reported effective treatment across case series. 4
Ondansetron may be tried but often demonstrates limited efficacy compared to its use in other conditions. 1, 2 Multiple studies note its suboptimal response in CHS. 4
Hot showers or baths provide temporary symptomatic relief and were cited as universally effective across all case reports. 4, 6 This compulsive hot water bathing behavior occurs in 44-71% of CHS patients and serves as both a diagnostic clue and temporary management strategy. 2, 3
Critical Medications to Avoid
Opioids must be avoided entirely as they worsen nausea, carry high addiction risk, and do not address the underlying pathophysiology. 1, 2, 3 Despite being mentioned in some case reports, opioids should not be considered first-line therapy. 7, 4
Long-Term Preventive Management
Pharmacologic Prevention
Tricyclic antidepressants, specifically amitriptyline, are the mainstay of long-term preventive therapy. 1, 2, 3 The dosing algorithm is:
- Start at 25 mg at bedtime 1, 2
- Titrate weekly by 25 mg increments 1
- Target minimal effective dose of 75-100 mg at bedtime 1, 2
- Monitor closely for efficacy and adverse effects 1
This recommendation comes from the 2024 American Gastroenterological Association guidelines and represents the strongest evidence for long-term management. 1
Essential Counseling
Cannabis cessation counseling is mandatory and should be initiated at every clinical encounter. 1, 2 Evidence shows that combining psychosocial interventions with pharmacology may be necessary for successful long-term management. 1 Recidivism rates are high, with many patients remaining uncertain about the role of cannabis despite recurrent episodes. 1
Diagnostic Approach Before Treatment
Rule Out Life-Threatening Conditions First
Before attributing symptoms to CHS, exclude acute abdomen, bowel obstruction, mesenteric ischemia, pancreatitis, and myocardial infarction. 1, 2, 3 CHS is frequently underdiagnosed or misdiagnosed due to limited clinician awareness. 3
Clinical Diagnostic Criteria
Suspect CHS when all three criteria are met: 1, 2
Clinical features: Stereotypical episodic vomiting with acute onset, occurring ≥3 times annually 1, 2
Cannabis use patterns: Duration >1 year before symptom onset, frequency >4 times per week on average 1, 2
Cannabis cessation: Resolution of symptoms after abstinence for ≥6 months or duration equal to 3 typical vomiting cycles 1, 2
Key Diagnostic Clue
Compulsive hot water bathing behavior (prolonged hot baths or showers for symptom relief) occurs in 71-92% of CHS patients and strongly suggests the diagnosis. 1, 2 While not pathognomonic (also seen in cyclic vomiting syndrome), it is a highly characteristic feature. 1
Common Pitfalls to Avoid
Do not rely on switching to lower THC/higher CBD formulations or edible forms as these strategies lack scientific validation. 1 Edibles deliver THC systemically just as effectively as smoking, and total THC dose—not delivery method—is the critical factor. 3
Do not underestimate recidivism risk. Despite diagnosis and counseling, many patients continue cannabis use and characterize symptoms as food-related rather than cannabis-related. 1
Do not use conventional antiemetic protocols. The American Gastroenterological Association and British Journal of Anaesthesia recommend multimodal antiemetic prophylaxis that differs from standard postoperative nausea and vomiting protocols. 3