Cyclic Vomiting Syndrome (CVS)

What is CVS?

Cyclic Vomiting Syndrome (CVS) causes recurrent, stereotyped episodes of intense nausea and vomiting separated by periods of feeling normal. Each child’s pattern tends to look similar each time (how it starts, how long it lasts, time of day). CVS itself is not caused by a blockage or infection, but we carefully rule out other conditions that can look similar.

Who is affected?

CVS can occur at any age but often begins in early childhood. Many children have a personal or family history of migraine, and CVS is considered part of the migraine spectrum.

Typical symptoms & pattern

- Sudden, severe nausea and vomiting that can last hours to a few days
- Episodes may start in the early morning
- Pallor, abdominal pain, headache, light/noise sensitivity, and fatigue are common
- Between episodes, children usually return to normal health
- Triggers can include poor sleep, illness, stress/anxiety, excitement, certain foods, or travel

Red flags—call your care team or seek urgent care: dehydration (no urination >8–12 hours, dry mouth, lethargy), severe belly pain with a swollen/firm abdomen, persistent vomiting that looks different than usual, or neurologic changes (severe headache with stiff neck, confusion, vision changes).

Why we do a workup (ruling out other diseases)

CVS is a clinical diagnosis based on the repeated pattern and normal health between episodes. Because other problems can cause vomiting, we may perform tests to rule out:
- Kidney/urinary issues: e.g., UPJ obstruction
- Intestinal rotation issues: malrotation/volvulus
- Neurologic causes: signs of increased intracranial pressure

Possible tests (tailored to symptoms):
- Blood work: blood count, electrolytes, celiac testing, thyroid testing
- Urine testing
- Imaging when indicated (abdominal ultrasound or upper GI series to look at rotation)
- Endoscopy is not always required, but may be considered if symptoms suggest another GI disease

Relationship to migraine

CVS is often described as a “migraine of the gut.” Many children with CVS have headaches or a family history of migraine. Treating the migraine component can reduce episodes.

Treatment goals

1) Stop or shorten episodes, 2) prevent dehydration, and 3) reduce how often episodes occur.

During an episode (acute care)

- Rest in a dark, quiet room; encourage small sips of clear fluids or oral rehydration solution
- Antinausea medicines (e.g., ondansetron as prescribed)
- Pain/headache support (per clinician guidance)
- If fluids can’t be kept down or there are red flags, IV fluids and medicines in urgent care/ER may be needed

Prevention between episodes (prophylaxis)

- Younger children: cyproheptadine (Periactin) is commonly used
- Older children/teens: amitriptyline is a first-line option
- Some patients may benefit from neurology consultation, especially when headaches are prominent or episodes are frequent/severe

Lifestyle supports

- Sleep: aim for 8–10 hours/night with consistent bed/wake times
- Nutrition: regular meals, less processed foods, steady hydration; identify and avoid food triggers (some families find benefit with dairy-free or gluten-free approaches if triggers suggest this)
- Mental health: counseling, treatment of anxiety/depression, and coping strategies can reduce episode frequency

Outlook

The good news: many children outgrow CVS or see episodes become less frequent over time, especially with treatment and trigger management. Having a plan for early treatment and hydration often shortens episodes and reduces ER visits.

Follow-up & monitoring

- Keep a simple episode diary (timing, triggers, response to medicines)
- Schedule periodic check-ins to adjust dosing and review growth/weight
- If new red flags appear or the pattern changes, your team may repeat testing or consider endoscopy when appropriate

Key points for families

- CVS causes repeated, similar vomiting episodes with normal health in between
- We perform a targeted workup to rule out UPJ obstruction, malrotation, and increased intracranial pressure
- Periactin (younger) and amitriptyline (older) are common preventive medicines; neurology consult can be helpful
- Good sleep, steady nutrition/hydration, and mental health care reduce episodes
- Many kids improve or outgrow CVS over time

References

 NASPGHAN. GI Kids: Patient Education Resources. North American Society for Pediatric Gastroenterology, Hepatology and Nutrition. https://www.gikids.org

 American Academy of Pediatrics (AAP). Pediatric Gastroenterology Clinical Reports and Patient Education. https://www.aap.org

 Blaufuss, T. Common Sense Pediatric GI: Practical Guidance for Families. Dakota Pediatric Gastroenterology, Fargo, ND, 2025.

 Li BU, Lefevre F, Chelimsky GG, et al. NASPGHAN Consensus Statement on the Diagnosis and Management of Cyclic Vomiting Syndrome. J Pediatr Gastroenterol Nutr. 2008;47(3):379-393.

 NASPGHAN. Cyclic Vomiting Syndrome. GI Kids.