If you don’t have irritable bowel syndrome (IBS), you probably don’t sense food moving through your digestive tract. But people with IBS can be very aware of it. And they can be more sensitive to discomfort during the process, says gastroenterologist Brian Baggott, MD.

Changes in digestive motility (movement) and sensitivity can cause common IBS symptoms: abdominal pain, gas, diarrhea and constipation. But that’s not all.

Symptoms you never suspected

“While intestinal, or bowel, problems are a trademark of IBS, symptoms can occur in any part of your digestive tract,” Dr. Baggott says.

If IBS affects your…

…esophagus, spasms can make it hard for you to swallow. You may feel like there’s a lump in your throat.

…stomach, poor motility can cause indigestion. That can feel like belly pain, bloating, nausea, a heartburn sensation, burping or regurgitation.

…biliary system (including your gallbladder and bile ducts), you can feel like you’re having a gallbladder attack. Bloating, nausea, vomiting and abdominal pain are symptoms.

…small intestine, spasms can cause gas and bloating.

…large intestine (colon), various symptoms can occur. You can have diarrhea if food residues run so swiftly through your large intestine that water doesn’t have time to be absorbed into your body. You can have constipation if food residues move too slowly.

Diagnosing IBS

“Diagnosing IBS can be difficult because symptoms are the same as many other digestive diseases,” Dr. Baggott says. “IBS is identified once we’ve ruled out other diseases. It’s a ‘diagnosis of exclusion.’”

When Dr. Baggott suspects a patient has IBS, he conducts testing throughout the digestive system. He may order a(n):

• Upper endoscopy. Using a long, thin scope, he can see inside the esophagus and stomach.
• CT enterography or a small bowel series. These sets of X-rays can help identify diseases in the small intestine.
• Colonoscopy. This test gives the most detailed look inside the large intestine.
• CT scan and blood tests. These tests can help diagnose problems outside your digestive tract that could be causing digestion problems.

“Having these tests can help make a definitive IBS diagnosis,” Dr. Baggott says. “While IBS is a diagnosis of exclusion, it is a real disease that has real treatments that can significantly improve your quality of life.”

One symptom that isn’t IBS

Sometimes people with IBS blame all of their digestive troubles on their disease. But that can be dangerous.

When new symptoms crop up, like weight loss or loss of appetite, always have them evaluated, advises Dr. Baggott.

“One symptom that IBS does not cause is bleeding,” he notes. “If you have rectal bleeding or bloody stools, it’s not IBS. Get to a doctor.”