Cyclic Vomiting Syndrome
Define:

• Stereotypical episodes of vomiting <1 week
• 3 episodes in past year, 2 in past 6 months, at least one week apart
• Absence of vomiting between episodes

3 Phases – Interepisodic, Prodromal, and Vomiting

Epidemiology:

• More common in children
• More frequent bouts in children (12/year) vs. adults (4/year)
• Broad age of onset for adults
• Symptoms longer for adults prior to diagnosis
• Nausea between episodes is more common in adults

Differential diagnosis:

ACUTE:

• Acute gastroenteritis (rotovirus, enteric aderovirus, norovirus)
• Post-operative nausea/vomiting
• Vestibular neuritis
• Chemotherpy/Drugs

CHRONIC:

• Pregnancy
• Chronic nausea/vomiting syndrome
• Gastroparesis
• Gastric outlet obstruction
• CVS
• Rumination syndrome

Cannabinoid Hyperemesis Syndrome
Define:

• Stereotypical episodic vomiting similar to CVS (onset, duration, frequency)
• Presentation after prolonged/excessive cannabis use
• Relief of symptoms with sustained (1 week) cessation of cannabis*

* often associated with pathologic bathing behavior (prolonged hot baths/showers) – considered pathognomonic for CHS