What is the appropriate treatment for cannabis hyperemesis syndrome?

Treatment for Cannabis Hyperemesis Syndrome

Intravenous or oral benzodiazepines (lorazepam 0.5–2 mg every 4–6 hours) are the most effective first-line acute treatment for CHS-related nausea and vomiting, followed by haloperidol or droperidol as second-line agents, with topical capsaicin 0.1% cream as adjunctive therapy—and complete cannabis cessation is the only definitive cure, requiring at least 6 months of continuous abstinence. 1

Acute Management in the Emergency Department

First-Line Therapy

• Benzodiazepines are the most effective acute treatment, specifically lorazepam 0.5–2 mg IV or PO every 4–6 hours, providing both antiemetic effects through sedation and anxiolytic properties that address the stress-mediated component of CHS. 1
• Multiple prospective studies demonstrate superior efficacy of benzodiazepines compared to standard antiemetics in CHS patients. 1

Second-Line Therapy

• Antipsychotics such as haloperidol or droperidol can reduce hospital length of stay by nearly 50% (6.7 hours vs 13.9 hours; p=0.014). 1
• Alternative antipsychotics include promethazine (12.5–25 mg every 4–6 hours) or prochlorperazine (5–10 mg every 6–8 hours), though these are less effective than haloperidol. 1

Adjunctive Therapy

• Topical capsaicin 0.1% cream applied to the abdomen activates TRPV1 receptors and provides consistent symptom relief. 1
• This should be applied with close monitoring for efficacy and adverse effects. 1

Medications to Avoid

• Opioids should never be used in CHS because they exacerbate nausea, carry high addiction risk, and do not address the underlying pathophysiology. 1
• Ondansetron may be tried for nausea, but efficacy is often limited in CHS patients. 1

Definitive Long-Term Management

Cannabis Cessation (The Only Cure)

• Complete and sustained cessation of cannabis is the only definitive cure for CHS. 1
• Symptom resolution requires at least 6 months of continuous abstinence (or a period equivalent to three typical vomiting cycles for that specific patient). 1
• Partial reduction of cannabis use or switching to edible forms does not lead to symptom improvement—full abstinence is mandatory. 1

Preventive Pharmacotherapy

• Tricyclic antidepressants, specifically amitriptyline, are the mainstay of long-term preventive therapy. 1
• Initiate at 25 mg at bedtime, increase by 25 mg weekly, targeting a maintenance dose of 75–100 mg at bedtime. 1
• This can be initiated even while working toward cannabis cessation. 1

Psychosocial Interventions

• Cannabis cessation counseling is mandatory for all patients with confirmed CHS. 1
• Referral to addiction medicine specialists or substance use counselors is essential, given the relapse rate exceeds 40% in reported series. 1
• Co-management with psychiatry is advisable given the high prevalence of anxiety and depression comorbidities in this population. 1
• Cognitive behavioral therapy or mindfulness meditation may improve overall quality of life. 1

Diagnostic Confirmation Before Treatment

Required Diagnostic Criteria (All Must Be Present)

• Cannabis exposure: ≥1 year of regular use (>4 times/week) preceding symptom onset. 1
• Clinical pattern: Stereotypical episodic vomiting occurring ≥3 times annually with acute onset lasting <1 week. 1
• Definitive confirmation: Complete symptom resolution after ≥6 months of continuous cannabis abstinence. 1

Highly Suggestive Features

• Compulsive hot-water bathing or showering for symptom relief is reported in 44–71% of CHS cases and is highly suggestive. 1
• Daily or near-daily cannabis use is documented in 68–97% of confirmed CHS cases. 1

Critical Differential Diagnosis

• Rule out life-threatening conditions first: acute abdomen, bowel obstruction, mesenteric ischemia, pancreatitis, and myocardial infarction before confirming CHS diagnosis. 1
• Distinguish from Cannabis Withdrawal Syndrome (CWS): CHS occurs during active cannabis use with vomiting, while CWS occurs after stopping cannabis (24–72 hours post-cessation) and requires opposite management. 1

Common Pitfalls to Avoid

• Unnecessary investigations: Once CHS is suspected, extensive diagnostic testing should be avoided, as it leads to unnecessary procedures and an average diagnostic delay of several years. 1
• Over-reliance on hot-water bathing as pathognomonic: Although present in up to 71% of CHS patients, similar behavior occurs in approximately 44% of cyclic vomiting syndrome cases, limiting its diagnostic specificity. 1
• Patient denial: Many patients attribute vomiting to food, alcohol, or stress rather than cannabis—clinicians must not accept this denial and should provide firm counseling on the cannabis-symptom link. 1
• Opioid prescription for abdominal pain: This worsens nausea and increases addiction potential in CHS patients. 1
• Repeated endoscopy: When EGD is performed soon after a CHS episode, findings such as mild gastritis, erythematous streaking, Mallory-Weiss tears, or esophagitis are consequences of vomiting, not primary pathology—repeated procedures should be avoided. 1

Supportive Care During Acute Episodes

• Basic laboratory workup should include complete blood count, serum electrolytes and glucose, liver function testing, and lipase. 1
• Intravenous fluid resuscitation for volume depletion from recurrent vomiting. 1

Prognosis and Follow-Up

• Complete and sustained cannabis abstinence is required for symptom resolution—partial measures are ineffective. 1
• Regular outpatient follow-up is critical to monitor for relapse, reinforce cessation strategies, and provide ongoing psychosocial support. 1
• Recidivism risk exceeds 40%, underscoring the need for ongoing addiction medicine support. 1