What causes IBS?
The precise cause of IBS isnโt always known, partly because it isnโt just one condition.
The cause can be genetic, stress, anxiety, oversensitivity of the gut, certain foods, infections (such as a severe case of gastroenteritis) or changes to your natural gut microbes. Though itโs often an intolerance to certain foods that triggers flare-ups.
There can also be other factors that play a role in IBS, including muscle contractions in the intestines, poorly coordinated signals between the brain and your intestines, and abnormalities in your nervous system. Early life stress, particularly in childhood, is also thought to have a connection to IBS.1
Research has also shown that the neurotransmitter serotonin may be important in the symptoms of IBS by altering the function of nerve cells in the bowel and causing changes in pain sensation and bowel function.2
What are the symptoms of IBS?
The symptoms of IBS can vary from person to person. Some of the most common symptoms of IBS include:
- Stomach pain or cramps
- Bloating
- Diarrhea
- A sudden urge to use the bathroom
- Constipation
These symptoms may get better or worse through the day, and usually link to whether youโve eaten and if youโve had a bowel movement.
Some other symptoms of IBS that people experience include:
- Gas
- Mucus in your stool
- Tiredness and feeling low on energy
- Nausea
- Back pain or muscle aches
- Urinary issues (you might need to go often, more than normal, have sudden urges to use the bathroom, or feel like you canโt fully empty your bladder)
- Not feeling in control of when you need to use the bathroom
- Incontinence
Can IBS lead to other problems?
Unless itโs being caused by a more severe condition, like inflammatory bowel disease (IBD) or celiac disorder (a severe intolerance to gluten in the body), itโs unlikely it will lead to anything more serious. If you have concerns about your symptoms, then itโs always best to speak to a doctor.
Some IBS symptoms can lead to other problems. Constipation can lead to hemorrhoids, for example, and diarrhea to dehydration and problems absorbing vitamins and minerals. These conditions and symptoms can have a major effect on your mental health, confidence, and feeling in control of your life.
Treated trusted source:
- Howell, S., et al. (2004). The Irritable Bowel Syndrome has Origins in the Childhood Socioeconomic Environment. Official journal of the American College of Gastroenterology | ACG, 99(8), pp.1572โ1578.
- Bruta, K., et al. (2021). The role of serotonin and diet in the prevalence of irritable bowel syndrome: a systematic review. Translational Medicine Communications, 6(1).
This page was medically reviewed by
Dr. Joseph Palumbo on December 01, 2025. Next review due on
December 01, 2028.
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