Cause of bladder problem still a mystery

Q: I have interstitial cystitis. Are there certain foods or drinks that I should avoid? And do any medications help?

A: Interstitial cystitis (IC) is a puzzling condition in which the bladder wall becomes irritated or inflamed, leading to frequent and often-painful urination. Most people with IC are women, who also may experience discomfort in the pelvic area and pain during sexual intercourse.

The symptoms of IC can be similar to those of a urinary-tract infection. That problem is caused by a bacterial infection in the bladder or urethra, the tube that carries urine from the bladder out of the body. Urinary-tract infections are much, much more common than IC. Most people get better quickly and recover fully with antibiotics.

But in IC, there is no infection, so antibiotics do not help. The cause remains a mystery. Some researchers believe the condition might be caused by an allergic or immune system reaction, a toxic substance in the urine or a nerve problem in the bladder wall.

Doctors sometimes refer people to a urologist if routine urine tests do not reveal bacteria despite lingering symptoms. To make a diagnosis, the urologist is likely to perform a test called a cystoscopy.

Some patients with IC find that they can reduce their discomfort by changing what they eat or drink. Caffeinated beverages (including coffee, tea and colas), alcohol, citrus fruits, tomatoes, spicy foods and chocolate are a few in a long list of foods that aggravate IC in some people. Each person needs to discover what she or he needs to avoid. Your best bet is to keep a journal to track your diet and symptoms to identify which foods and beverages seem to make your symptoms worse.

Another treatment for IC is bladder training. You teach yourself to urinate on a regular schedule rather than only when you feel the urge. This may help lessen problems with frequent urination but does not ease pain.

As for medications, only one drug, Pentosan polysulfate sodium (Elmiron), has been FDA approved for treating IC. About 30 percent of people with IC have fewer symptoms while taking this medication. Side effects are uncommon. Many other drugs that are not specifically approved for IC may offer pain relief. They include ibuprofen (Advil, Motrin and others), naproxen (Aleve, Naprosyn and others), aspirin and acetaminophen (Tylenol and others). Doctors also may prescribe certain antidepressants, such as amitriptyline (Elavil, Endep) or antiseizure medications that are used to treat chronic pain, such as gabapen-tin (Neurontin) and carbamazepine (Tegretol, Atretol and others). Hydroxyzine (Atarax), an antihistamine-like prescription medication, has also helped some IC sufferers.

Some people with IC find relief with bladder distention or bladder washing. In bladder distention, a doctor places a tube into the bladder through the urethra and injects sterile water into the bladder to stretch it. Most patients feel worse for a couple of weeks after the procedure. After that, 30 percent to 50 percent of patients feel better. But the benefit lasts only three months, and the procedure is done under general anesthesia, which carries a small risk of its own.

A bladder wash entails filling the bladder with a sterile solution that contains various substances, such as heparin (an anticlotting medication) or DMSO (a solvent that reduces pain and swelling). After a period of time, the person empties his or her bladder. As with other therapies, success is variable. Repeating the procedure risks causing more irritation of the bladder wall and introducing infection.

Another possible therapy for IC is electrical nerve stimulation. Traditionally, this has been done with a device called a TENS (transcutaneous electrical nerve stimulator) unit. Mild electrical impulses are passed into the body through wires placed below the navel, on the lower back or inside the rectum or vagina. The patient controls the timing and intensity of these electrical impulses, which may relieve symptoms by increasing blood flow to the bladder. In the past few years, a new device called an InterStim has been available. It stimulates a single nerve root that connects to the bladder and is used mainly for treating other urinary problems, such as the inability to hold urine. As such, it may help IC patients who have frequent urination problems that have not responded to other treatments.

There are so many treatment options because no one program is highly effective. More research is needed. Until scientists find the cause of IC and doctors improve its treatment, a trial-and error approach is often best. Start with the simplest program and move on to more difficult or experimental options only if you need more help. Many IC patients need the help of a specialist, but all should try to help themselves by trying dietary changes first.

The Harvard Medical School Adviser is researched and written by the faculty and staff of Harvard Medical School. Visit www.health.harvard.edu/adviser.