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Irritable Bowel Syndrome (IBS) Health Center

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Treating Irritable Bowel Syndrome (IBS) and Diarrhea

Over-the-Counter (OTC) Medicines for IBS continued...

In a 2002 comprehensive report by the American College of Gastroenterology, researchers found these drugs to be effective with slowing diarrhea. These drugs, however, did not help with other IBS symptoms such as abdominal pain or swelling.

Side effects of these treatments include abdominal cramping, discomfort and enlargement, along with dry mouth, dizziness, and constipation.

If you take an antidiarrheal drug, use the lowest dose possible, and don't take it for an extended period of time, advises the Mayo Clinic.

Other OTC products such as Pepto-Bismol, antacids, and medicines for gas relief are generally safe. Some antacids, particularly those containing magnesium, can cause diarrhea, however.

Never take any over-the-counter medicine long term without consulting with your doctor, and return to your doctor for follow-up care, says J. Patrick Waring, MD, a gastroenterologist at Digestive Health Care of Georgia. He notes that IBS symptoms can be caused by other more serious problems. Make sure your symptoms are not caused by another illness.

Prescription Drugs for IBS

Doctors may prescribe antidepressants for the abdominal pain associated with IBS. This does not necessarily mean that you are depressed. Low doses of antidepressants are known to block signals of pain to the brain.

For people with IBS diarrhea, doctors will likely recommend a low dose of a type of antidepressant called tricyclic antidepressants such as Pamelor, Elavil, and Tofranil. These drugs don't cause diarrhea like some of the newer antidepressants, such as Celexa, Paxil, and Prozac.

Common side effects of these antidepressants include dry mouth, blurred vision, and constipation.

Studies show that tricyclic antidepressants can improve abdominal pain, says Philip Schoenfeld, MD, MSEd, MSc. He is co-author of the American College of Gastroenterology's treatment guidelines.

When IBS patients come into her office, Beth Schorr-Lesnick, MD, FACG, a gastroenterologist at the Montefiore Medical Center in Bronx, New York, tries to review each individual's symptoms to determine the right treatment. Many times, she starts off patients with an antispasmodic drug such as Levbid or Bentyl.

Antispasmodics "relax the smooth muscle of the gut," says Schorr-Lesnick. She says muscle spasms and gas in the gut cause much of the pain IBS. Sometimes, she prescribes the antispasmodic and antidepressant together to relieve abdominal cramping.

Side effects of most antispasmodics include decreased sweating, constipation, and dryness of the mouth, nose, throat, or skin. The American College of Gastroenterology guidelines found that there isn't enough evidence to make a recommendation about antispasmodics.

On the other hand, the experts found that the prescription drug Lotronex to be effective for treatment of all symptoms associated with IBS with diarrhea, including abdominal pain and distress, urgency, and diarrhea. The finding, however, was only relevant to female patients.

Lotronex works to block the body chemical serotonin's effect on the digestive system. Serotonin's role in the development of IBS is uncertain, but researchers do know Lotronex somehow calms down the colon and slows down the frequency of bowel movements.

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