What is cyclic vomiting syndrome (CVS)?

Cyclic vomiting syndrome (CVS) is a condition in which a person suffers from sudden, repeated attacks of severe nausea, vomiting, and exhaustion. These symptoms come from no apparent cause. Each attack can last from a few hours to several days. Attacks may be so severe that the patient is bedridden or must go to the emergency room or hospital. Often, the symptoms start early in the morning. Following an episode, the patient is free of symptoms and returns to normal health.

Both males and females of any age may be affected. CVS may last for months, years, or decades. However, symptoms do not occur each day. The attacks may take place anywhere from several times a year to several times a month. If a patient is having daily symptoms for weeks or a month, these are not due to cyclic vomiting syndrome.

The symptoms, time of day, frequency, severity, and length of each episode of CVS are usually the same for any one person. However, these may be different from patient to patient.

Who is affected by cyclic vomiting syndrome (CVS)?

CVS is more common in children than adults. About 3 of every 100,000 children are diagnosed with CVS. In most cases in children, CVS starts to occur between the ages of 3 and 7. However, the disorder can begin at any age from infancy through old age.

What causes cyclic vomiting syndrome (CVS)?

There is no known cause of CVS, but mitochondria in the cells may have a role. Mitochondria act as the cells’ digestive system, taking in nutrients and then breaking them down and forming energy that can be used by the cells. Mitochondrial DNA can become abnormal because of illness, a genetic condition inherited from the mother, or exposure to certain drugs or toxins. Often, tests suggest subtle changes in the mitochondrial function and exact diagnosis is not found. Cyclic vomiting may also occur more commonly in a patient who has a parent with migraines.

The following also could play a role in CVS:

  • Migraine headaches, which appear in up to 80% of children and 25% of adults with CVS.
  • Problems with how food travels through the digestive system.
  • Problems with brain, spinal cord, or nervous system control over the body’s gastrointestinal tract responses.
  • Hormone imbalances.

What can trigger an episode of cyclic vomiting syndrome (CVS)?

Anxiety, a panic attack, or something that is emotionally upsetting may bring on CVS. Also, the following may trigger CVS:

  • Respiratory or sinus infections or the flu.
  • Reactions to certain foods such as chocolate or cheese, caffeine, or the food additive MSG (monosodium glutamate).
  • Changes of season (symptoms are more common in fall and winter).
  • Menstrual periods.
  • Motion sickness.
  • Overeating, fasting, or eating immediately before bedtime.
  • Physical exhaustion.

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

Some of the symptoms of CVS are:

  • Repeated episodes of severe nausea, retching (attempting to vomit), and vomiting.
  • Heaving or gagging.
  • Lack of appetite.
  • Sensitivity to light.
  • Pain in the abdomen.
  • Pale appearance to the skin.
  • Severe fatigue.
  • Severe headaches.
  • Not wanting to talk.
  • Drooling or spitting.
  • Extreme thirst.
  • Low-grade fever (up to 101 degrees Fahrenheit).
  • Diarrhea.