What is the treatment for cyclic vomiting syndrome related to Tetrahydrocannabinol (THC) intoxication?

Treatment of THC-Related Cyclic Vomiting Syndrome

The definitive treatment for THC-related cyclic vomiting syndrome (cannabinoid hyperemesis syndrome) is complete cessation of cannabis use for at least 3-6 months. 1

Diagnosis and Recognition

Cannabinoid Hyperemesis Syndrome (CHS) can be identified by:

• Stereotypical episodic vomiting in a patient with cannabis use for >1 year
• Cannabis use frequency >4 times per week
• Relief from hot showers/baths (a pathognomonic feature)
• Resolution of symptoms after cannabis cessation 1, 2

Acute Management Algorithm

First-Line Interventions

1. IV fluid rehydration to correct dehydration and electrolyte abnormalities 1

2. Dopamine receptor antagonists:

   • Haloperidol 0.5-2 mg IV or PO every 4-6 hours (most effective) 1
   • Other options: droperidol 3

3. Symptomatic relief methods:

   • Hot showers/baths (temporary relief)
   • Topical capsaicin cream to abdomen 1
   • Quiet, darker room environment 3

4. Antiemetic combinations:

   • Ondansetron (available in sublingual form)
   • Promethazine or prochlorperazine (available as rectal suppositories) 3

5. Sedation strategies:

   • Benzodiazepines (e.g., lorazepam 0.5-2 mg PO/SL/IV every 6 hours)
   • Alprazolam (available in sublingual and rectal forms) 3, 1

Second-Line Options

1. Non-narcotic pain control: IV ketorolac (preferred over opioids) 3
2. Additional medications:
   • Olanzapine (5-10 mg PO daily)
   • Corticosteroids 1

Monitoring Considerations

• QT interval prolongation with certain medications
• Acute dystonic reactions
• Sedation levels 1

Recovery Phase Management

• Focus on electrolyte-rich fluids (sports drinks)
• Nutrient drinks as tolerated
• Expect 1-2 days for recovery phase 3

Long-Term Management

Patient Education

1. Explain that complete cannabis cessation is the only definitive treatment
2. Warn that symptoms typically recur when cannabis use is reinitiated 2, 4
3. Discuss potential fatal outcomes if condition remains untreated 5

Follow-up Considerations

• Monitor for symptom resolution (typically occurs within weeks to months of cannabis cessation)
• Screen for cannabis withdrawal symptoms
• Provide support for maintaining abstinence

Important Caveats

• Avoid narcotic pain medications except in the most severe refractory cases, as they may worsen symptoms 3
• Do not delay treatment while awaiting confirmation of diagnosis 1
• Rule out life-threatening conditions with basic workup (CBC, electrolytes, glucose, liver function tests, lipase, urinalysis) 1
• Recognize paradoxical effects - despite THC's traditional anti-emetic properties, chronic use can cause this paradoxical hyperemesis syndrome 6
• Watch for dehydration and electrolyte abnormalities which can become severe 7

Pitfalls to Avoid

1. Misdiagnosis: CHS is often confused with Cyclic Vomiting Syndrome, leading to delayed diagnosis and unnecessary testing 6
2. Ineffective treatments: Traditional antiemetics often show limited effect in CHS 8
3. Overlooking cannabis use: Always ask specifically about cannabis consumption in patients with cyclic vomiting 7
4. Continuing cannabis: Failure to emphasize complete cessation will result in symptom recurrence 2, 4

Remember that despite the increasing legalization and medical use of cannabis, CHS remains a serious condition that requires prompt recognition and appropriate management with cannabis cessation as the cornerstone of treatment.