What Is Cyclic Vomiting Syndrome?

Cyclic vomiting syndrome (CVS) is a condition that causes repeated bouts of nausea and vomiting over several hours or days. CVS is much more common in children and is estimated to affect about 2% of school-aged kids. It usually begins between ages 3 and 7 and it is more likely to occur in girls than boys.

This article explains the symptoms, causes, and triggers of cyclic vomiting syndrome. It also talks about how CVS is diagnosed and treated.

Cyclic Vomiting Syndrome Symptoms

Children with CVS usually have episodes or cycles of nausea, vomiting, and gagging that last between a few hours to a few weeks. Children might gag while brushing their teeth, looking at food, thinking about food, or smelling food.

During an episode, children may also be less active and have a decreased appetite. They may want to stay home instead of being with other kids to avoid the embarrassment of vomiting in front of them.

Unless a child also has viral gastroenteritis ("stomach flu"), the symptoms of CVS do not include fever, diarrhea, pain, or respiratory symptoms.

Symptoms that can go along with nausea and vomiting in CVS include:

• Abdominal discomfort
• Headache
• Pale skin
• Sunken eyes due to dehydration

Once the episode is over, children are usually symptom-free until the next time it happens.

Most children with CVS will outgrow it during adolescence. In some cases, however, it can continue throughout adolescence and into adulthood. Even though it usually starts in childhood, it may start at any age. Many people who had CVS as a child go on to develop migraines in adulthood.

Phases of Cyclic Vomiting Syndrome

An episode of cyclic vomiting syndrome goes through four distinct phases. The cycles can continue for several hours, days, or weeks. Usually, the symptoms go away for a while before they start up again.

Phases of CVS include:

• Prodrome: The child might feel sick, dizzy, or mildly nauseated.
• Vomiting: The child will have nausea, vomiting, gagging, and might be unable to keep down food and drink.
• Recovery: Your child might start to feel better, with an increased appetite, but still might not feel completely better.
• Well phase: Symptoms of CVS have stopped. Your child should avoid certain foods or other triggers until they feel fully recovered.
  

After a few episodes of CVS, a child or their parents may be able to sense when an episode is coming on. This can help them identify what may have triggered it so they can avoid those triggers in the future.

Causes

It is believed that CVS causes problems with gastrointestinal (GI) function due to abnormalities in the connection between neurons in the brain and the GI system (or "gut"). It is not caused by a virus or another disease of the GI system.

Most children with this condition have a family history of migraines. Many experts believe the two are related. In fact, cyclic vomiting syndrome is sometimes referred to as an abdominal migraine.

Triggers

Usually, CVS comes on due to certain triggers. Generally, a child who has CVS will be sensitive to specific triggers and not to others. Here are some common CVS triggers:

• Stress—sometimes children and their parents might not recognize that a child is experiencing stress, with CVS being the only symptom
• Being tired, sleepy, or jet-lagged
• Certain odors, especially the smell of a food the child dislikes
• Motion sickness—this can be caused by riding in a car, airplane, boat, or rollercoaster.
• Stomach flu—while CVS is not viral gastroenteritis, sometimes a child can experience cyclic vomiting during or after stomach flu
• Becoming overheated or overexcited

Diagnosis

Cyclic vomiting syndrome is classified as a functional GI disorder. This means there is nothing wrong with the physical structure of the GI system. Instead, the diagnosis is made by looking at the typical pattern of symptoms. There aren't any specific tests that can confirm the diagnosis.

A doctor will also want to rule out other disorders that could cause the same symptoms as CVS. (This is called a differential diagnosis.)

Conditions that can cause similar symptoms include:

• Viral gastroenteritis
• Gastroesophageal reflux disease (GERD)
• Certain metabolic disorders
• Brain tumors
• Addison disease
• Malrotation of the intestine with volvulus, a condition where the bowel moves around and becomes tangled
  

Tests that may be done include:

• Brain imaging tests, such as computerized tomography (CT) scan or magnetic resonance imaging (MRI)
• Metabolic tests
• Abdominal ultrasound
• Upper gastrointestinal X-ray series with small bowel follow-through (UGI-SBFT), in which images are taken of the esophagus, stomach, and small intestine
  

Sometimes a healthcare provider will suggest treating symptoms as if they are caused by CVS. If the child responds to the treatment, this can confirm a CVS diagnosis.

Treatment

The acute phase of CVS is the phase during which symptoms are actively occurring. The goal of acute treatment is to prevent problems such as dehydration. Chronic treatment is focused on preventing more episodes from recurring over the long term.

Acute Treatment

During an acute episode of vomiting, treatment is aimed at making your child as comfortable as possible.

Treatments may include:

• Resting in a quiet, dark room
• Medications such as Zofran (ondansetron), Imitrex (sumatriptan), Catapres (clonidine), or benzodiazepines, which can prevent nausea and vomiting
• Sugary drinks

If your child becomes severely dehydrated, they may need to receive intravenous (IV) fluids in the hospital.

Chronic Treatment

The best treatment for cyclic vomiting is prevention. Medications that are used to treat migraines in children are also used for preventing cyclic vomiting. These include:

• Periactin (cyproheptadine)
• Inderal (propanolol)
• Elavil (amitryptylline)
  

Avoiding Triggers

If your child is diagnosed with CVS, you may want to try to identify triggers that bring on these episodes.

Some people with migraine keep a headache journal to record what triggered a specific migraine episode. Likewise, keeping a CVS journal may help you identify triggers of CVS episodes. This can help you avoid them if possible.

Riboflavin

Researchers have investigated the possibility of using the B vitamin riboflavin for the prevention of cyclic vomiting. It's known that riboflavin is sometimes helpful for preventing migraine headaches. Riboflavin is found in whole grains as well as almonds, spinach, and mushrooms. It also comes in supplement form.

A small European study in 2016 found that treating children who had been diagnosed with CVS with riboflavin for 12 months helped to improve the condition. While this study is far too small to make riboflavin a standard treatment, you may want to ask your pediatrician if adding this vitamin to your child's treatment plan could be helpful.

Summary

Cyclic vomiting syndrome is a disorder that causes episodes of vomiting and nausea. It can occur over a period of hours, days, or sometimes weeks. CVS is more common in children than in adults. CVS is diagnosed mainly by ruling out other diseases that have similar symptoms. Often, children with CVS develop migraines as adults.

A Word From Verywell

While cyclic vomiting syndrome can be unpleasant and disruptive, most children who have CVS outgrow their symptoms. Knowing how to how to manage vomiting in children can keep them from getting too dehydrated. If your child has recurrent episodes of CVS, talk to their pediatrician. Preventive medications, such as those used for migraines, can be very effective for CVS as well.