What are the causes of cyclic vomiting syndrome (CVS)?

From the Guidelines

Cyclic vomiting syndrome should be managed by identifying and avoiding personal triggers, using preventive medications such as tricyclic antidepressants or anticonvulsants, and providing supportive care during acute episodes, including intravenous fluids, antiemetics, and sedatives, as recommended by the most recent clinical practice update 1.

Key Considerations

• The condition is characterized by recurrent episodes of severe nausea and vomiting, with symptom-free periods in between, and is often triggered by psychological and physiological factors, including stress, sleep deprivation, and hormonal fluctuations 1.
• Patients may exhibit self-soothing behaviors, such as hot water bathing or showering, which can provide temporary relief but may also lead to burns or other complications 1.
• The pathophysiology of cyclic vomiting syndrome is not fully understood but may involve abnormal brain-gut interactions, mitochondrial dysfunction, or autonomic nervous system irregularities 1.

Management Strategies

• Preventive medications, such as tricyclic antidepressants like amitriptyline (starting at 10-25mg daily) or anticonvulsants like topiramate (25-100mg twice daily), can help reduce the frequency and severity of episodes 1.
• During acute episodes, treatment should include intravenous fluids for dehydration, antiemetics like ondansetron (4-8mg every 6 hours) or promethazine (12.5-25mg every 6 hours), and sedatives such as lorazepam (0.5-2mg) to help with anxiety and nausea 1.
• Patients should be encouraged to identify and avoid personal triggers, maintain a regular sleep schedule, eat small frequent meals, and practice stress management techniques to help prevent episodes 1.

Diagnostic Considerations

• Cyclic vomiting syndrome should be suspected in patients with recurrent episodes of severe nausea and vomiting, and a thorough medical history should be taken to identify potential triggers and rule out other underlying conditions 1.
• The Rome IV criteria for cyclical vomiting syndrome in adults can be used to guide diagnosis, which includes at least 3 discrete episodes in the previous year, absence of nausea and vomiting between episodes, and supportive remarks such as a history or family history of migraine headaches 1.

From the Research

Definition and Characteristics of Cyclic Vomiting

• Cyclic vomiting syndrome (CVS) is a disorder characterized by recurrent episodes of severe nausea and vomiting separated by symptom-free periods 2.
• It is a chronic disorder of gut-brain interaction characterized by recurrent disabling episodes of nausea, vomiting, and abdominal pain 3.
• CVS affects both children and adults with a prevalence of approximately 2% in the United States, and it is more common in female individuals and affects all races 3.

Diagnosis of Cyclic Vomiting

• The diagnosis of CVS is based on the Rome criteria, and minimal recommended testing includes an upper endoscopy and imaging studies of the abdomen 3.
• Diagnostic tests of exclusion remain essential, including an upper gastrointestinal (GI) contrast study to exclude intestinal malrotation and basic laboratory screening 4.
• An abdominal ultrasound is recommended to exclude renal hydronephrosis in children and biliary disease in adults 4.

Treatment and Management of Cyclic Vomiting

• Tricyclic antidepressants are the main treatment for controlling symptoms of CVS 2, 5.
• Prophylactic therapy consists of tricyclic antidepressants (amitriptyline), antiepileptics (topiramate), and aprepitant in refractory patients 3, 5.
• Abortive therapy consists of triptans, antiemetics (ondansetron), and sedation 3, 5.
• Treatment of comorbid conditions such as anxiety, depression, migraine headache, autonomic dysfunction, sleep disorders, and substance use is extremely important to improve overall patient outcomes 3, 5.

Lifestyle and Non-Pharmacological Interventions

• Lifestyle and non-pharmacological interventions play a pivotal role in successful management of CVS 4.
• Techniques like meditation, relaxation, and biofeedback may be offered as complementary therapy to improve overall well-being and patient care outcomes 5.
• Eliminating and addressing trigger factors are an essential part of management of CVS 2.