What Are the Symptoms of IBS?

People with IBS have symptoms that can include:

• Diarrhea (often described as violent episodes of diarrhea)
• Constipation
• Constipation alternating with diarrhea
• Belly pains or cramps, usually in the lower half of the belly, that get worse after meals and feel better after a bowel movement
• A lot of gas or bloating
• Harder or looser stools than normal (pellets or flat ribbon stools)
• Bloating sensation: a belly that sticks out

Stress can make symptoms worse.

Some people also have urinary symptoms or sexual problems.

What are the types of IBS?

There are four types of the condition. There is IBS with constipation (IBS-C) and IBS with diarrhea (IBS-D). Some people have an alternating pattern of constipation and diarrhea. This is called mixed IBS (IBS-M).  Other people don’t fit into these categories easily, called unsubtyped IBS, or IBS-U.

What are the causes of IBS?

While there are several things known to trigger IBS symptoms, experts don’t know what causes the condition.

Studies suggest that the colon gets hypersensitive, overreacting to mild stimulation. Instead of slow, rhythmic muscle movements, the bowel muscles spasm. That can cause diarrhea or constipation.

Some think that IBS happens when the muscles in the bowels don’t squeeze normally, which affects the movement of stool. But studies don’t seem to back this up.

Another theory suggests it may involve chemicals made by the body, such as serotonin and gastrin, that control nerve signals between the brain and digestive tract.

Other researchers are studying to see if certain bacteria in the bowels can lead to the condition

Because IBS happens in women much more often than in men, some believe hormones may play a role. So far, studies haven’t borne this out.

How is IBS diagnosed?

There are no specific lab tests that can diagnose IBS. Your doctor will see if your symptoms match with the definition of IBS, and he may run tests to rule out conditions such as:

• Food allergies or intolerances, such as lactose intolerance and poor dietary habits
• Medications such as high blood pressure drugs, iron, and certain antacids
• Infection
• Enzyme deficiencies where the pancreas isn’t releasing enough enzymes to properly digest or break down food
• Inflammatory bowel diseases like ulcerative colitis or Crohn’s disease