Irritable bowel syndrome (IBS) is a common disorder that affects the digestive system, causing symptoms such as irregular bowel movements and abdominal (stomach) pain. IBS affects approximately 11% of people worldwide and roughly 20% of people in the U.S.
IBS is a chronic disease—meaning it can last for years as symptoms persist. People with IBS may find that their symptoms fluctuate over time, or even day to day. You might go through several cycles of flare-ups (periods where symptoms are active) and remission (periods where you experience little to no symptoms).
There are multiple types of IBS—all of which relate to your bowel movements. Some people with IBS experience constipation, while others with the condition often have diarrhea. However, it’s also possible to have mixed or alternating bowel habits, which can cause cycles of both constipation and diarrhea.
These symptoms can be frustrating, so it’s important to keep a log of what you’re experiencing to help your healthcare provider figure out the treatment options that are right for you.
Everyone experiences IBS a little differently and the type of IBS you have can differ from someone else's journey with the condition. That said, there are some hallmark symptoms of IBS which include:
- Abdominal pain: The pain can range from mild to severe and may feel like cramps, dull aches, discomfort, or a combination of all three. Stomach pain usually gets better after passing a bowel movement, but may worsen after eating a big meal or if you’re experiencing emotional stress.
- Change in bowel movements: IBS can cause diarrhea, constipation, or both. With diarrhea, you might have loose or watery stools, while constipation may feel like stool is difficult to pass.
- Bloating: Changes in your bowel movements or having gas can make you feel full or give you a tight stomach.
- Incomplete bowel movement: This can occur when you feel like you didn’t completely empty your system after going to the bathroom.
- Mucus: You might also notice milky white-colored mucus in the toilet when you pass stool.
Symptoms by Type of IBS
There are three primary types of IBS which are based on whether you more often experience diarrhea, constipation, or both. Keep in mind: it’s important to identify the type of IBS you have as this can guide treatment, but not everyone’s experience fits neatly into one type—and that’s OK.
IBS with constipation—or IBS-C—is a type of IBS that occurs when you experience constipation as your primary change in bowel movements. Specifically, you might have IBS-C if more than 25% of your stool is hard or lumpy and less than 25% of your stool is loose or watery.
With this condition, you might experience less than three bowel movements per week and have pain or strain while passing stool.
Diarrhea that accompanies IBS—known as IBS-D—causes the opposite effect of IBS-C symptoms. People with IBS-D have more than 25% of watery and loose stool and less than 25% of hard or lumpy stool. Research estimates that 80% of people who seek care for IBS have the IBS-D type. National Institute of Diabetes and Digestive and Kidney Diseases. Definition & facts for irritable bowel syndrome.
If you have this type of IBS, you might also experience an urgency to use the bathroom and dehydration, alongside diarrhea. In contrast to constipation, IBS-D may cause you to pass loose stool three or more times a day.
Sometimes, people with IBS can experience both diarrhea and constipation. Diarrhea and constipation don’t typically occur together or happen on the same day—rather, you might notice your bowel habits alternate. This condition is known as IBs with mixed bowel habits, otherwise called IBS-M.
Symptoms of IBS-M include experiences of both loose and watery stools and hard and lumpy stools, dull or sharp pain before or during bowel movements, and changes in how often you’re using the bathroom.
Sometimes, other symptoms can accompany changes in bowel movements and stomach pain. While these symptoms don’t always occur, you might also experience:
- Gas such as flatulence (farting) or belching (burping)
- Heartburn or acid reflux
- Nausea and vomiting
- Muscle and lower back pain
- Lowered appetite
- Sleep problems
- Pain during sexual intercourse
Symptoms in Women
IBS, specifically IBS-C, is more common in women than men. Women with IBS report higher levels of fatigue, anxiety, and depression than men with IBS.
Studies suggest that hormonal changes due to menstruation can trigger these sex differences in symptoms. Specifically, research shows that IBS symptoms can become more severe just before or during menstrual periods. You may experience an increase in abdominal pain, bloating, and frequency of bowel movements during menstruation. and rectal sensitivity all increase during menstruation.
On the other hand, these differences may not entirely be biological. Women are also one to three times more likely to report IBS symptoms than men, which means that healthcare providers and experts alike may have more information about IBS in women. Research suggests that this may occur due to general help-seeking behavior differences between sexes—meaning, women are generally more open to seeking medical care than men.
Health recognizes that not everyone who is female was born with female reproductive organs and that not everyone who is male was born with male reproductive organs. Health also recognizes that people may not identify as any one sex or gender. The information in this article is based on how researchers present their results, and the gender- and sex-based language used most accurately reflects their research design and outcomes.
When to See a Healthcare Provider
While IBS symptoms can be uncomfortable, it’s rare for your symptoms to need urgent attention. However, some situations may call for immediate medical care. You should reach out to your healthcare provider as soon as possible if you experience:
- Diarrhea for more than two days (or 24 hours for infants, toddlers, and young children)
- Six or more loose stools in 24 hours
- Severe abdominal (stomach) or rectal (butt) pain
- Black or tarry stools or blood in your stools
- Severe dehydration
- Fever above 102 degrees Fahrenheit
- Frequent vomiting
A Quick Review
Irritable bowel syndrome (IBS) is a condition that commonly causes abdominal pain and changes in bowel movements, such as constipation, diarrhea, or both. It’s common to also experience symptoms such as bloating, gas, nausea, or heartburn.
If you think you have symptoms of IBS or may be at risk for the condition, it’s a good idea to talk to your healthcare provider about treatment options. While symptoms are not usually a major cause of concern and don’t prompt the need to visit your healthcare provider often, you should seek medical care immediately if you have severe pain, blood in your stool, or a high fever.
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National Institute of Diabetes and Digestive and Kidney Diseases. Symptoms & causes of irritable bowel syndrome.
National Institute of Diabetes and Digestive and Kidney Diseases. Definition & facts for irritable bowel syndrome.
International Foundation for Gastrointestinal Disorders. Overview of symptoms.
Kim YS, Kim N. Sex-gender differences in irritable bowel syndrome. J Neurogastroenterol Motil. 2018;24(4):544-558. doi:10.5056/jnm18082
Pati GK, Kar C, Narayan J, et al. Irritable bowel syndrome and the menstrual cycle. Cureus. 2021;13(1):e12692. doi: 10.7759/cureus.12692
National Institute of Diabetes and Digestive and Kidney Diseases. Symptoms & causes of diarrhea.