Cyclical vomiting syndrome
Cyclical vomiting syndrome, or CVS, is a rare condition that typically starts during childhood and causes repeated episodes of sickness, vomiting, and nausea. The complete cause of CVS is unknown, but the vomiting episodes are not because of any infections or illness. The condition gets better as the child gets older, but rarely, it can also affect adults. However, the condition can be frightening; there are possible ways to manage it through medications and lifestyle changes.
Cyclical vomiting syndrome symptoms
People with CVS can feel very sick and might vomit for hours or even days in some instances. They usually recover from those episodes and feel better, but they might have another episode within a month or in further future. CVS can also last for months, years, or even decades. Some may require hospital treatments due to severe symptoms.
An episode of cyclical vomiting syndrome has four phases:
Prodrome phase
Where the person will:
- Feel a vomiting episode is about to begin
- Have nausea and intense sweating for a few minutes to hours
- Appear unusually pale
Vomiting phase
Where the person might:
- Vomit up to six times in an hour for days
- Have abdomen pain
- Be unable to move or talk
- Develop other symptoms like diarrhea, dizziness, headache, a high temperature, headache, sensitivity, drooling, spitting, or feeling sleepy

Recovery phase
Where:
- Vomiting, nausea, and retching stops
- The person will see some improvement in other symptoms
Well phase
During the well phase, there will be no CVS symptoms
So, the cycle is typically predictable, with the same routine symptoms at the same time of the day or night.
CVS causes
- Emotional stress (including panic attacks)
- Physical stress
- Certain foods and drinks (including caffeine, alcohol, and MSG)
- Extremely cold or hot weather
- Allergies
- Periods
- Motion sickness
- Overeating
CVS complications
Severe CVS episodes can lead to:
- Dehydration
- Inflammation
- Tear in food pipelining
- Tooth decay
- Gastroparesis
Consult a doctor for treatment if you or your child come across severe nausea or vomiting.
Reviewed by – Dr. Priyanka, MBBS MD Microbiology
Page last reviewed: 16 JULY 2022