Once regarded as a figment of the imagination, interstitial cystitis (in-ter-STIH-shul-sist-EYE tiss) or I-C is now known to be a real disease. Unlike regular cystitis, I-C is a not a bladder infection, but rather a chronic inflammation of the bladder walls. Ninety percent of sufferers are women. Symptoms mimic those of a urinary tract infection, including constant pain or pressure in the bladder, and an ever-present urge to urinate, though little urine may be in the bladder. However, antibiotics have no effect. It's not certain what causes I-C, or how to cure it. Some doctors believe it may result because the protective lining inside the bladder is damaged or absent, or from irritating substances in the urine. The condition varies from mild to serious, where the patient may need to urinate every 20 minutes. To diagnose I-C, a physician must first rule out other causes, such as bacterial infection, sexually transmitted disease, endometriosis (en-doe-mee-tree-OH-sis), and cancer. Then, he or she looks inside the bladder with a cystoscope, checking for hemorrhages on the bladder wall, a characteristic sign. A biopsy may also be done. In addition, the doctor may expand the bladder with water. For some patients, this procedure can relieve symptoms for several months. Other treatments include the use of medication, with new solutions currently being sought. For the latest information on I-C, contact a health provider in your area.