Phase I/II Randomized, Placebo-Controlled Study of Capsaicin for Interstitial Cystitis and Vulvar Vestibulitis

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.