Dimethyl sulfoxide (DMSO) is a chemical compound that was first made in 1866 by a Russian scientist. It is a colorless liquid penetrates the skin and other membranes easily without damaging them. This quality makes it an excellent compound for carrying other compounds into the body.
Its use has been tried for everything from muscle and joint pain to bladder infections. So far, the Food and Drug Administration (FDA) has approved its use only for the palliative treatment of interstitial cystitis (painful bladder syndrome). It was recently approved for study in the treatment of swelling associated with traumatic brain injury.
It might interest you to know that some studies have shown that a topical form of nonsteroidal antiinflammatory drug called diclofenac added to a base of DMSO and applied to the skin around the knee has been shown safe and effective for use with mild-to-moderate knee osteoarthritis. It has a bit of a drying effect on the skin but skin lotions can counteract that side effect.
One of those studies compared the use of DMSO alone with topical diclofenac. As a result of this study, we have some proof that the DMSO is not an effective agent for knee osteoarthritis. Topical nonsteroidal agents have the distinct advantage of reducing the adverse gastrointestinal effects that occur more commonly with oral (pill) forms of these medications.