What is the primary treatment for cannabinoid hyperemesis syndrome (CHS) in a young to middle-aged adult with a history of chronic marijuana use?

Primary Treatment for Cannabinoid Hyperemesis Syndrome

The definitive treatment for cannabinoid hyperemesis syndrome is complete and permanent cessation of all cannabis use, which is the only intervention that leads to long-term resolution of symptoms. 1, 2

Acute Management in the Emergency Department

When a patient presents with active vomiting, the immediate treatment approach should follow this hierarchy:

First-Line Acute Therapy

• Benzodiazepines, specifically lorazepam, are the most effective acute treatment for CHS-related nausea and vomiting based on multiple prospective studies. 2, 3

Second-Line Acute Therapy

• Haloperidol or droperidol should be used as second-line agents when benzodiazepines are insufficient or contraindicated, as these butyrophenones can reduce hospital length of stay by nearly 50% (6.7 vs 13.9 hours). 4, 2

Adjunctive Acute Therapy

• Topical capsaicin 0.1% cream applied to the abdomen provides consistent symptom relief by activating TRPV1 receptors and should be used alongside primary antiemetics. 1, 2
• Hot showers or baths provide temporary symptomatic relief and serve as a diagnostic clue (present in 44-71% of cases). 1, 2

Medications to Avoid

• Never use opioids as they worsen nausea, carry high addiction risk, and do not address the underlying pathophysiology. 1, 3
• Ondansetron may be tried but often has limited efficacy compared to its use in other conditions. 1, 3

Diagnostic Confirmation

Before initiating treatment, confirm the diagnosis using these criteria:

• Stereotypical episodic vomiting occurring ≥3 times annually during active chronic cannabis use 1, 2
• Cannabis use >1 year before symptom onset with frequency >4 times per week 1, 2
• Compulsive hot water bathing behavior (present in 44-71% of cases, though not entirely specific) 2, 3
• Rule out life-threatening conditions first: acute abdomen, bowel obstruction, mesenteric ischemia, pancreatitis, and myocardial infarction 1, 3

Critical Distinction: CHS vs Cannabis Withdrawal Syndrome

This distinction is essential because they require opposite management strategies:

• CHS occurs during active chronic cannabis use and requires cessation 4, 3
• Cannabis Withdrawal Syndrome (CWS) occurs 24-72 hours after stopping cannabis in heavy users and may require supportive care with gabapentin, nabilone, or nabiximols 4, 3

Definitive Long-Term Management

Cannabis Cessation Counseling

• Counsel patients that complete resolution requires at least 6 months of continuous cannabis abstinence, or an abstinence duration equal to at least 3 typical vomiting cycles for that specific patient. 1, 2, 5
• Symptoms will recur if cannabis use is reinitiated, so permanent cessation is necessary. 5, 6

Preventive Pharmacotherapy

• Tricyclic antidepressants, particularly amitriptyline, are the mainstay of long-term preventive therapy. 1, 2
• 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, 3

Psychological Support

• Provide cannabis cessation counseling and psychological support, as anxiety and depression are common comorbidities. 1, 3
• Consider co-management with psychiatry for patients with extensive psychiatric comorbidity or treatment resistance. 1

Common Pitfalls to Avoid

• Do not pursue exhaustive investigations once CHS is suspected—focus on making an early diagnosis to facilitate treatment. 3
• Do not underestimate the minimum cessation period—patients must understand that 3-6 months of complete abstinence is required to confirm diagnosis and achieve symptom relief. 5
• Patient skepticism is a major barrier—many patients believe cannabis helps their symptoms (paradoxically, it causes them), so strong counseling about the causal relationship is essential. 7
• Recognize that CHS prevalence is rising with cannabis legalization and increased potency of THC products, making this diagnosis increasingly common in emergency departments. 4, 7

Perioperative Considerations

For patients with known CHS requiring surgery:

• Enhanced prophylactic antiemetic therapy is recommended perioperatively due to increased risk for post-anesthesia intractable vomiting. 2
• Consider additional PONV prophylaxis for patients consuming >1.5 g/day inhaled cannabis, >20 mg/day THC oil, or >300 mg/day CBD oil. 4, 2
• Anticipate higher anesthetic requirements to achieve adequate depth of anesthesia and higher postoperative analgesic requirements using multimodal non-opioid strategies. 2