Prospective study of intravesical dimethyl sulfoxide in treatment of suspected early interstitial cystitis.

The efficacy of intravesical instillations of dimethyl sulfoxide (DMSO) in the treatment of suspected early interstitial cystitis was investigated in a prospective study. Among 20 patients treated, complete symptomatic remissions were achieved in 3, partial symptomatic remissions were achieved in 16, and 1 had no symptomatic improvement. However, functional bladder capacities following treatment were increased by more than 25 per cent in only 4 cases. Among 16 patients who experienced symptomatic remissions and who have been followed for greater than or equal to four months, 14 had sustained remissions (mean follow-up eleven months) and 2 had unsustained remissions. Clinically apparent toxicity was minimal but transient elevation of the serum lactic acid dehydrogenase was occasionally observed during treatment. DMSO appears to be useful in the management of carefully selected patients with suspected early interstitial cystitis.