Clinical practice update advises on management of cyclic vomiting syndrome
A basic workup for episodic vomiting should include bloodwork and urinalysis, and management of cyclic vomiting syndrome often entails multiple abortive medications, the American Gastroenterological Association said.
Clinician should consider cyclic vomiting syndrome (CVS) as a potential diagnosis in any adult presenting with the core clinical feature of episodic bouts of repetitive vomiting, according to a clinical practice update from the American Gastroenterological Association.
Although there are effective treatments for most patients, the condition remains underdiagnosed and undertreated, according to the update. Most patients experience years of diagnostic delays, futile investigations, and unneeded surgeries. One-half of those with the condition visit the ED at least annually, and one in three becomes disabled. Early recognition and appropriate treatment can reduce symptoms and improve quality of life, the update said. It was published July 16 by Gastroenterology.
CVS has four phases: interepisodic, prodromal, emetic, and recovery, the update said. About 65% of patients experience prodromal symptoms, lasting a median of one hour, before the onset of vomiting. Some patients report an impending sense of doom, most report panic, and many are unable to communicate effectively during this phase, the update noted. Prodromal and emetic phases can be associated with fatigue, feeling hot or cold, mental fog, restlessness, anxiety, headache, bowel urgency, acute diarrhea or constipation, abdominal pain, diaphoresis, flushing, or shakiness or tremulousness, it said.
The prodromal phase is the ideal time to deliver abortive therapies, and earlier intervention is associated with a better chance of aborting an episode. Patient education on this point is imperative to optimal care, the update said. The emetic phase is characterized by uncontrollable bouts of retching and vomiting that can last for hours to days. Patients may also drink large amounts of water or even stick their fingers in their throat to vomit for temporary relief, according to the update. Clinicians should not deem these behaviors as malingering, as it is a self-soothing pattern that appears to be specific to CVS, the update stated.
A basic workup for episodic vomiting should include bloodwork (complete blood count, serum electrolytes and glucose, liver function testing, and lipase) and urinalysis, the update advised. One-time esophagogastroduodenoscopy or upper GI imaging could exclude obstructive lesions that might cause the episodic nausea and vomiting.
Many patients with CVS use cannabis to alleviate symptoms, and expert consensus states that cannabinoid hyperemesis syndrome (CHS) can be ruled out at six months or at least three typical cycle lengths after cannabis cessation. Patients using cannabis are often stigmatized by the health care system, and all patients, including those with ongoing cannabis use and uncertainty about the diagnosis of CVS versus CHS, should be offered abortive and/or prophylactic therapy, the update said.
Mental health clinicians can help patients with comorbid conditions associated with CVS, such as anxiety or depression, migraines, sleep disorders, and substance use, according to the statement. Addressing these underlying conditions by means of pharmacologic and/or nonpharmacologic therapies, such as cognitive behavioral therapy or mindfulness meditation, can substantially improve CVS symptoms and overall quality of life. Patients should attempt to identify and mitigate or avoid CVS triggers by taking steps such as getting regular sleep, avoiding prolonged fasting, and pursuing stress management techniques, the update noted.
Prophylactic therapy is indicated for those with more than four episodes of moderate to severe CVS per year, each of which lasts two or more days and is associated with ED visits or hospitalizations. Tricyclic antidepressants are strongly recommended as first-line prophylactic medications, and topiramate, aprepitant, zonisamide, and levetiracetam are effective second-line agents, the update said. The probability of aborting an episode is highest when medications are taken as early into the prodromal phase as possible, but abortive therapy is particularly challenging for patients who move quickly from the interepisodic to the emetic phase without a prodrome, according to the update.
Although some patients respond to monotherapy, nearly all patients with CVS require two or more agents to reliably abort attacks, the statement said. Most common abortive treatment regimens include sumatriptan and an antiemetic agent, such as ondansetron. Sedation is often an effective abortive strategy in CVS, and promethazine may be useful, the statement said. Other sedating agents, such as diphenhydramine or benzodiazepines, may also be needed in an "abortive cocktail" of medications, according to the statement. Patients with CVS also respond to sedating antipsychotic medications such as droperidol and haloperidol, although these are typically reserved for use in the ED.
If a patient cannot abort an episode at home, then going to an ED for IV fluids and IV abortive therapy is reasonable, the update said. In the recovery phase, which usually lasts one to two days, the priority is to consume electrolyte-rich fluids or nutrient drinks. Patients in the recovery phase may feel nauseated or have dyspeptic symptoms but generally can tolerate moderate volumes of liquid intake, the update said.
"CVS is a common and disabling condition in adults, but need not be so, as it is a treatable condition," the update concluded. "Prompt recognition remains the key factor in avoiding unnecessary investigations and providing patients with effective treatments."