Irritable Bowel Syndrome (IBS) Symptoms

Medically Reviewed by Zilpah Sheikh, MD on January 28, 2024
4 min read

Irritable bowel syndrome (IBS) is a condition that affects the gastrointestinal (GI) tract -- your stomach and intestines -- and can cause chronic pain in your abdomen, cramping, and discomfort.

Along with abdominal cramping and discomfort, IBS symptoms may include:

  • Bloating
  • Gas
  • Constipation -- your poop comes out either lumpy or hard
  • Diarrhea -- your poop is loose or watery
  • Episodes of constipation and diarrhea
  • Poop that feels urgent, difficult to pass, or incomplete
  • Clear or white mucus with your poop
  • Food intolerance/sensitivity to FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) or carbs that are hard to digest
  • Joint pain
  • Tiredness, as being tired can make your GI troubles worse; not getting good quality sleep leads to a "flare", which in turn leads to low-quality sleep
  • Brain fog
  • Stress

To confirm that your digestive problems are truly IBS, doctors need to see two of the following three features:

  • Stomach pain, bloating, or cramping linked to having a bowel movement
  • There's a change in how often you poop
  • The poop looks different

The standard diagnostic guideline for IBS, known as the Rome IV criteria, requires that you have had these symptoms for at least 1 day a week in the last 3 months and that symptoms started at least 6 months prior. But most doctors don't follow that requirement closely, says Philip Schoenfeld, MD, co-author of the American College of Gastroenterology's IBS treatment guidelines.

Schoenfeld says it's tough for patients to remember the exact number of weeks they had symptoms in the preceding year. He suggests that people should not wait but rather see a doctor whenever they have recurrent symptoms.

Doctors can confirm whether your symptoms are IBS or signs of another problem. IBS is often confused with other illnesses, so doctors will need to ask questions and perform tests or procedures to confirm a diagnosis, like: 

  • a stool test
  • CT scan
  • colonoscopy
  • upper endoscopy
  • test for bacteria overgrowth
  • lactose intolerance test  

Can IBS cause blood in your stool?

Blood in your poop, fever, and weight loss are NOT symptoms of IBS. If you have these symptoms, see a doctor right away.

Your doctor may ask you to keep an IBS symptom journal. This record can help you and your doctor figure out what triggers your IBS and how to deal with those triggers.

Remember, a variety of factors can set off IBS, including certain types of food, the volume of food, stress, medicines, your menstrual cycle, and your environment.

You may find, for instance, that you tend to feel bloated after eating snacks during office meetings. Knowing what influences your eating and what causes you distress can help you develop prevention strategies.

Fill this out as soon as you experience symptoms. Print extra copies to have on hand.

Date/Time symptoms began   
Date/Time symptoms ended   
Description of symptoms (pain, bloating, diarrhea, constipation, etc.)   
Where were you and what were you doing when the symptoms started?   
Pre-symptom activity   
Type of food eaten   
Amount of food eaten (Rate 1-10 with 10 as an excessive portion.)   
Medications taken   
Suspected trigger(s)   

If your symptoms continue for 3 months or more, see your doctor. Contact your doctor right away if you have the following symptoms in addition to other IBS symptoms:

  • Nighttime diarrhea
  • Weight loss
  • Bleeding from your rectum
  • Pain that doesn't go away with gas or pooping
  • Weight loss
  • Vomiting that can't be explained


IBS symptoms vary from person to person but can include gas, constipation, stomach pain, and diarrhea. Triggers can happen frequently or from time to time. Although IBS is a chronic condition, it can be managed by making changes to your diet and other habits. Talk to your doctor if you have typical IBS symptoms coupled with fever, vomiting, strong stomach pain, diarrhea, or bleeding from your rectum.

  • What are the first symptoms of an IBS flare? Some of the first symptoms include irregular periods, having gas when you eat certain foods, and how your stomach feels when you're stressed.
  • How long do IBS symptoms last? If you have IBS, your symptoms can appear often or from time to time after certain triggers (known as flare-ups). IBS is a long-term condition.
  • What foods trigger IBS symptoms? Foods that include wheat (gluten), dairy products, and foods that usually cause gas can all cause IBS symptoms.
  • Are IBS symptoms the same for people assigned female at birth (AFAB) and people assigned male at birth? Women or people AFAB are twice as likely to have IBS. Women/people AFAB can have worse symptoms or flare-ups during their menstrual cycle.