Dimethyl sulfoxide is metabolized in man by oxidation to dimethyl sulfone or by reduction to dimethyl sulfde. Dimethyl sulfoxide and dimethyl sulfone are excreted in the urine and feces . Dimethyl sulfoxide is eliminated through the breath and skin and is responsible for characteristic odor from patients on dimethyl sulfoxide medication. Dimethyl sulfone can persist in serum for longer than two weeks after a single intravesical instillation. No residual accumulation of dimethyl sulfoxide has occurred in man or lower animals who have received treatment for protracted periods of time. Following topical application, dimethyl sulfoxide is absorbed and generally distributed in the tissues and body fuids.