Expert Q&A: Cyclic vomiting syndrome

Sad woman sitting on the bathroom floor

Cyclic vomiting syndrome (CVS) is a chronic disorder of gut-brain interaction (DGBI) characterized by recurrent episodes of severe nausea, vomiting and often abdominal pain. It can be accompanied by other symptoms, such as excessive sweating, hot and cold flashes, diarrhea and sometimes headaches.

CVS begins abruptly and usually occurs out of the blue, lasting hours to several days or even a week. In between episodes, individuals have periods of normal health, without any symptoms or can have some nausea and occasional abdominal discomfort at baseline. These symptom-free intervals can last for weeks to months.

If you’re vomiting daily for more extended periods, it might be caused by something other than CVS. However, if left untreated, people with CVS may experience longer and more frequent episodes, potentially leading to a condition called coalescent CVS, in which the typical “normal” or “inter-episodic” phase is lost.

CVS affects people of all ages, from ages 2 to even those in their 70s and 80s. The severity and duration vary from person to person, but episodes for each individual are typically consistent.

Who can be affected by CVS?

Two percent of the population in the United States have cyclic vomiting syndrome. The disorder affects people of all ages, but patients are most often in thier 20s to 40s. This is likely because CVS is triggered by stress, and these are stages of life when people are most likely to experience significant life stress, such as job placement, family and career responsibilities.

CVS seems to affect women more than men (about 60% women and 40% men), and it affects all races and ethnicities.

How is CVS diagnosed?

CVS is diagnosed by a set of internationally accepted clinical criteria called the Rome Criteria. Episodes of vomiting must occur at least three times a year and have occured at least twice in the last six months.

There are no biomarkers to diagnose CVS, meaning we haven’t identified a molecule found in blood, fluid or tissue that can indicate a normal or abnormal process. Instead, we determine if you have CVS by your symptoms.

All the following must occur for the last 12 months to be considered for a diagnosis of CVS:

  • Stereotypical episodes of vomiting that are abrupt in onset, last less than one week and occur at least one week apart
  • Three or more episodes in the past year, including two episodes in the past six months
  • No nausea or vomiting between episodes (except for some mild symptoms)
  • No metabolic, gastrointestinal or structural central nervous system or biochemical disorders

What can CVS be confused with?

Twenty years ago, cyclic vomiting was typically diagnosed only in children. Today, gastroenterologists are more aware that CVS can affect patients of all ages. However, CVS can still be misdiagnosed as gastroparesis — a stomach disorder where food slowly enters the small intestine. Patients are often told that they have gastroenteritis or other unlikely diagnoses.

It can also be misdiagnosed as gallbladder disease. Unfortunately, about 30% of people who have CVS can undergo gallbladder surgery in an attempt to relieve symptoms.

CVS is strongly associated with migraines, which can involve vomiting. However, migraines are characterized by severe headaches, while CVS is characterized by severe vomiting.

Do you have migraines with vomiting, or is it cyclic vomiting symdrome?

Cyclic vomiting syndrome vs. cannabinoid hyperemesis syndrome

Cannabinoid hyperemesis syndrome (CHS) has symptoms similar to CVS. Because many people with CVS use cannabis products to reduce symptoms, patients with CVS are told that their symptoms could be caused by cannabis. It's difficult to tell the disorders apart, but stopping use of cannabis should lead to CHS symptoms going away.

Experts think that CHS is a subset of CVS. It’s possible that, for some, cannabis in low doses and used sparingly may relieve nausea and vomiting. But daily or near-daily use — particularly cannabis concentrates with high concentrations of THC — could make vomiting worse.

What triggers CVS?

Everyone with CVS has different triggers. Some common ones include the following:

  • Lack of sleep
  • Stress — both positive and negative.
  • Menstrual periods
  • Infections
  • Alcohol

Unlike migraine, reactions to food like caffeine, chocolate or MSG are rare.

How do you manage a vomiting episode with CVS?

The first step to managing cyclic vomiting syndrome is identifying your triggers. Sleep deprivation and stress are some common ones.

Learning how to recognize the first signs of a CVS episode can help stop or lessen its severity. These can include symptoms like intense nausea, pale skin, excessive salivation or abdominal pain. Some people feel an impending sense of doom and know that they're going to have an attack. Medicine taken at the first sign of symptoms can keep CVS from getting worse.

Once a full-blown episode begins, an oral meltaway medication that your body can absorb even with vomiting can be helpful.

Other medications such as sumatriptan via a nasal spray can also stop a CVS episode. Resting in a quiet, dark room can also help.

If you experience signs of dehydration from CVS, you should go to the emergency department, infusion clinic or urgent care for an IV infusion.

Daily medications called prophylactic therapy can reduce the frequency and severity of CVS attacks for moderate-to-severe CVS.

Is CVS a lifelong condition?

CVS is a chronic disorder that can be managed but doesn’t go away. However, some seniors with CVS have outgrown vomiting and instead develop episodes of migraine headaches. A large proportion of children with CVS outgrow symptoms but develop migraine headaches or chronic abdominal pain.

Medication and other treatments, like behavioral therapy and meditation, can help manage the symptoms of CVS.

Can CVS be fatal?

Cyclic vomiting syndrome is not a life-threatening condition. However, it’s important to note that severe episodes of vomiting can lead to complications like severe dehydration and acute kidney injury. Some patients can develop suicidal ideation, particularly if they’re unable to find a doctor who cares for patients with CVS.

Can people with CVS have a healthy pregnancy?

People with CVS can have a healthy pregnancy, although they may experience more severe vomiting during pregnancy. For others, vomiting goes away while pregnant. We need more studies to understand how CVS affects pregnancy and vice versa.

Ohio State can help you manage cyclic vomiting syndrome with the latest treatment advancements

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