Irritable bowel syndrome (IBS) is an intestinal disorder marked by unpleasant gastrointestinal symptoms. Its symptoms are similar to the symptoms of a wide variety of abdominal problems, some of which can be very serious.

It’s important to be diagnosed correctly because different conditions require different treatments. There’s no single definitive test to diagnose IBS, so other conditions must be ruled out before treatment can be started.

Symptoms of IBS tend to be triggered by stress and can worsen after meals. They can include:

  • change in bowel habits
  • stools that are watery, hard, lumpy, or contain mucus
  • diarrhea, constipation, or a combination of both
  • a feeling that bowel movements are incomplete
  • abdominal bloating, cramping, excess gas, and pain
  • heartburn or discomfort after eating normal-sized meals
  • frequent bathroom emergencies
  • lower backache

IBS doesn’t cause permanent damage to the intestines, nor does it increase cancer risk. The biggest issue is discomfort. Depending on the severity of symptoms, IBS may also disrupt your everyday routine.

Symptoms not associated with IBS include:

  • excessive unexplained weight loss
  • intestinal bleeding or blood in the stool
  • increased urination
  • fever
  • anemia
  • inflammation of the colon
  • vomiting

Don’t attempt to self-diagnose if you think you have IBS and have some of the symptoms listed above. Talk to your healthcare provider.

IBS is often confused with inflammatory bowel disease (IBD). The names may sound similar, but they aren’t the same and require very different treatment approaches.

IBD is a group of chronic or recurring diseases of the gastrointestinal tract. In IBD, the immune system malfunctions, attacking cells in the intestines. The body responds by sending white blood cells to the intestinal linings, resulting in chronic inflammation.

The two most common forms of IBD are Crohn’s disease and ulcerative colitis.

Although many symptoms are similar to those of IBS, people with Crohn’s and ulcerative colitis are more likely to have fever, rectal bleeding, weight loss, and a decrease in appetite. People with IBD have an increased risk of colon cancer.

Ulcerative colitis can also cause the following:

  • bloody stools
  • appetite loss
  • anemia
  • skin lesions
  • joint pain
  • eye inflammation
  • liver disorders

Early diagnosis is important, as complications can be serious.

Some types of cancer can cause a few of the same symptoms as IBS. Diagnostic testing can rule these out. Unlike IBS, colon cancer can cause rectal bleeding, bloody stools, and marked weight loss.

Symptoms of ovarian cancer include appetite loss and lack of energy. Women with ovarian cancer may notice their clothes feeling tight due to increased abdominal girth.

Such symptoms don’t normally show up until the advanced stages, which makes early detection even more critical.

Other conditions can also produce similar symptoms to IBS. For example:

  • Celiac disease is a digestive disorder triggered by gluten. This is a protein found in barley, rye, and wheat. In addition to other symptoms, celiac disease can cause vomiting, weight loss, and foul-smelling stool. It may also lead to anemia, bone or joint pain, seizures, and rash.
  • Diverticulosis doesn’t always produce noticeable symptoms, other than bloating. However, diverticulosis can turn into diverticulitis which means these areas of the colon can get infected and inflamed causing abdominal pain, a change in bowel habits, fever, chills and even bloody stools.
  • Endometriosis and IBS share many symptoms, especially pelvic pain. Endometriosis occurs when hormone-responsive tissue that is supposed to be inside the uterus, somehow becomes attached to other areas of the body, most often the intestines. It can result in abdominal cramping, painful periods, painful intercourse, and bleeding between periods along with many other symptoms depending on the location of the abnormal endometrial tissue.
  • Heartburn tends to cause a burning sensation behind the breastbone, usually after meals, when lying down, or bending over.
  • Dyspepsia can cause discomfort in the upper abdomen, sometimes after eating, but not related to using the bathroom.
  • Lactose intolerance means your body can’t tolerate lactose, the sugar found in milk. According to the National Institute of Diabetes and Digestive and Kidney Diseases, symptoms last 30 minutes to two hours after eating milk-based products. In addition to bloating, gas, and diarrhea, you may also feel nauseated.

IBS has no one single cause and may exist with other conditions which makes diagnosis extremely difficult. Other conditions might be mistaken for IBS because of its notoriety.

Keeping track of your symptoms can help your doctor decide which tests are needed to reach a diagnosis. Report anything unusual to your healthcare provider right away.

You may be referred to a gastroenterologist if IBS is suspected or to rule out other possible gastrointestinal (GI) conditions.