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Irritable bowel syndrome (IBS): the symptoms, getting a diagnosis, food, and treatment
For anyone with belly pain and bowel changes that keep coming back, anyone just told it is IBS, and parents of a child with belly pain that keeps returning. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK, part of the NIH) says irritable bowel syndrome is a group of symptoms that occur together: repeated pain in the abdomen and changes in bowel movements, which may be diarrhea, constipation, or both, without visible signs of damage or disease in the digestive tract. It says about 12% of people in the United States have it. This page passes on, by name, what NIDDK says: the symptoms and the three types, what causes it and who gets it more, how doctors diagnose it in adults and children and the warning signs of something else, food changes, and treatment. It builds the words to say to a doctor, and prints a card to keep.
Right now
- A lot of blood from the rectum, black and tarry stools with dizziness or fainting, or sudden, severe belly pain: call 911 or go to the emergency room (ours). Belly pain that could be appendicitis.
- Any blood in the stool, black stools, or weight loss you cannot explain? NIDDK says these may point to another health problem instead of IBS. See a doctor soon (ours).
- Thinking about suicide? Call or text 988, any time.
More help
- Other belly troubles: An upset stomach: find the right page · Constipation in adults · Constipation in a child · Celiac disease · Lactose intolerance · Heartburn and acid reflux · Food poisoning and stomach bugs.
- What can be part of it: Anxiety · Depression · After something terrible happened · Fibromyalgia · Period diary · When you can’t sleep.
- Food, care and costs: When you need food · When you need a doctor and can’t pay · My medicines list · Symptom diary · Get ready for your appointment.
- 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, nurse or dietitian has reviewed it. The facts were read on October 16, 2026 on NIDDK’s Irritable Bowel Syndrome (IBS) pages (NIH): the overview, Definition & Facts, Symptoms & Causes, Diagnosis, Treatment and Eating, Diet, & Nutrition (last reviewed November 2017), and Irritable Bowel Syndrome in Children (last reviewed November 2019). Ours: calling 911 or going to the emergency room for a lot of blood, black and tarry stools with dizziness or fainting, or sudden severe belly pain; seeing a doctor soon for any blood, black stools or weight loss; that it is real and not your fault; not starting, stopping or changing a prescribed medicine on your own; a symptom diary and changing one thing at a time; health centers, food banks and SNAP when money is tight; 988; and the order of the steps. What we left out: the names and brands of the single prescription medicines NIDDK lists, doses and amounts, research studies, and clinical pages for providers. This page saves nothing and loads no trackers.