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Cyclic vomiting syndrome: the episodes, the phases, and what helps
For anyone who keeps having bouts of severe nausea and vomiting that come and go, with weeks or months of feeling fine in between; for the parent of a child who does; and for anyone just told “it might be cyclic vomiting syndrome.” The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK, part of the NIH) says cyclic vomiting syndrome causes sudden, repeated episodes of severe nausea and vomiting that can last from a few hours to several days; that each episode tends to start at the same time of day and to be like the ones before; and that treatment depends on the phase. This page passes on, by name, what NIDDK says: the signs, the four phases and when to get help, who is more likely to get it and what can come with it, how doctors find it, treatment phase by phase, and the triggers, sleep, food and drink between episodes. It builds the words to say to a doctor, and prints a card for your plan.
Right now
- Someone is fainting or cannot be woken, is confused, has trouble breathing, or is vomiting blood or what looks like coffee grounds? Call 911 (ours). Do not drive yourself. GI bleeding.
- Very thirsty with a dry mouth, urinating less, dark urine, sunken eyes or cheeks, or light-headed during the vomiting? NIDDK says these are signs of dehydration: seek medical help right away. Ours: if you cannot reach your doctor, go to the emergency room. For a baby or child: the signs in a child.
- It is all too much, or you are thinking of ending your life? Call or text 988, any hour (ours).
More help
- The stomach, on this site: Gastroparesis · Heartburn and acid reflux · Irritable bowel syndrome · GI bleeding · Belly and stomach: find the right page.
- What can go with it: Migraine · Anxiety · Panic attacks · Depression · When you can’t afford a dentist.
- Children: Vomiting and diarrhea in a baby or child.
- Day to day: Symptom diary · My medicines list · Get ready for your appointment · Can’t sleep? · When drinking or drugs have become a problem.
- Care and costs: When you need a doctor and can’t pay · When a medical bill is too much.
- In a crisis: Help right now (988, 911). All our free tools.
An upset stomach, and not sure this is the right page? The pages on this site for throwing up, diarrhea, heartburn and constipation, on one list.
This page and its wording were written with AI (Claude) for Scarlet Beast (our AI policy). No doctor or nurse has reviewed it. The facts were read on October 17, 2026 on NIDDK’s Cyclic Vomiting Syndrome pages (NIH): the overview, Definitions & Facts, Symptoms & Causes, Diagnosis, Treatment and Eating, Diet, & Nutrition, and their Spanish versions; all were last reviewed in December 2017 and say the same things. Ours: 911 for fainting or someone who cannot be woken, confusion, trouble breathing, or vomiting blood or what looks like coffee grounds; the emergency room if you need help right away and cannot reach your doctor; a written plan made with the doctor before the next episode; telling the doctor honestly about marijuana; asking before starting a supplement; that it is real and not your fault; 988 when it is too much; health centers when money is tight; and the order of the steps. What we left out: the brand names of medicines (one NIDDK names has since been taken off the U.S. market), doses, research studies, and clinical pages for providers. This page saves nothing and loads no trackers.