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Learning About Cyclic Vomiting Syndrome

What is it?

An adult or child who has cyclic vomiting syndrome (CVS) has repeated bouts of severe vomiting and nausea. Between the vomiting episodes, the person's health is normal. The cause of CVS isn't known, but it may be related to migraine headaches.

What happens when you have CVS?

CVS causes severe nausea, vomiting, and drooling. You may not be able to walk or talk during an episode. You may look pale. You may have a fever and feel very tired and thirsty. Some people with CVS have belly pain and diarrhea.

Bouts of vomiting can last for a few hours or a few days. People with this condition tend to have a typical pattern of attacks. For example, one person may have bouts of CVS 4 times a year and always in the morning. Another person may have 8 bouts a year and always in the evening.

Some people with CVS have triggers that set off the vomiting. People have reported an infection, such as a cold, as a trigger. Other triggers include stress, menstrual cycles, and certain foods like chocolate or cheese. Children tend to have more triggers than adults do.

How is CVS treated?

Treatment is centred around easing the nausea and vomiting. The doctor may prescribe medicine.

During very bad bouts of vomiting, your doctor may want you to stay in the hospital for a while. You may get fluids through a vein (I.V.) to prevent dehydration. Dehydration can be serious. Your body needs fluids to make enough blood. Without a good supply of blood, vital organs such as the heart and brain can't work as well as they should.

When should you call for help?

Call your doctor now or seek immediate medical care if:

  • You have new or worse belly pain.
  • You have a fever.
  • You are vomiting.
  • You cannot pass stools or gas.
  • You have symptoms of dehydration, such as:
    • Dry eyes and a dry mouth.
    • Passing only a little urine.
    • Feeling thirstier than usual.

Watch closely for changes in your health, and be sure to contact your doctor if you have any problems.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

Where can you learn more?

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