OBJECTIVES: I. Estimate the optimal safe dose of intravesical capsaicin in patients with interstitial cystitis.

II. Evaluate the efficacy of 0.025% topical capsaicin in relieving chronic burning pain in patients with vulvar vestibulitis.

III. Evaluate the effect of capsaicin on type C nerve fibers in bladder mucosa and vulvar skin.

IV. Evaluate the effect of C fiber depletion on urinary levels of histamine and prostaglandin.

PROTOCOL OUTLINE: This is a randomized study. Patients with interstitial cystitis are randomly assigned to 1 of 3 pain control therapies.

The first group is treated with capsaicin. A second group is given individually titrated doses of capsaicin: the dose is increased as tolerated or until symptomatic response is acceptable. A control group receives a placebo. Therapy for all groups is administered intravesically every week for 5 weeks.

Patients with vulvar vestibulitis are randomly assigned to 1 of 2 pain control therapies. One group applies topical capsaicin cream to the painful area 4 times a day for 6 weeks. The dose is individually titrated if burning discomfort persists and the patient is compliant with the application schedule. The control group applies a placebo.

Patients with vulvar vestibulitis may continue or cross to capsaicin for 6 additional weeks.

PROTOCOL ENTRY CRITERIA:

--Disease Characteristics-- Women with interstitial cystitis by National Institute of Diabetes and Digestive and Kidney Diseases criteria Vulvar vestibulitis by International Society for the Study of Vulvar Disease, i.e.: Severe pain on touch or attempted entry of vagina Tenderness to pressure within the vulvar vestibule Vulvar erythema Duration of symptoms at least 6 months Absence of vulvovaginal infection, i.e.: No fungus No trichomonas No chlamydia No gonorrhea No "clue cells" in vaginal discharge