DMSO, or dimethyl sulfoxide, has a long history as a topical anti-inflammatory agent. One double-blind trial used a 10% DMSO gel topically on patients with tendinitis of the elbow and shoulder and found that it significantly reduced pain and inflammation in each joint.¹ Other preliminary^2,3 and double-blind^4,5 trials found DMSO to be effective in treating tendinitis, but one double-blind trial found no difference between the effects of a 70% DMSO solution and a 5% DMSO placebo solution.⁶ Certain precautions must be taken when applying DMSO, and it should only be used under the guidance of a qualified healthcare professional.

The use of DMSO, a colorless, oily liquid primarily used as an industrial solvent, for therapeutic applications is controversial. However, some evidence indicates that dilutions, when applied directly to the skin, have anti-inflammatory properties and inhibit the transmission of pain messages by nerves, and in this way might ease the pain of minor injuries such as sprains and strains.^7,8,9 However no controlled research exists to confirm these effects in sprains and strains. DMSO comes in different strengths and different degrees of purity. In addition, certain precautions must be taken when applying DMSO. For those reasons, DMSO should be used only with the supervision of a doctor.

The use of dimethyl sulfoxide (DMSO) for therapeutic applications is controversial in part because some claims made by advocates appear to extend beyond current scientific evidence, and in part because topical use greatly increases the absorption of any substance that happens to be on the skin, including molecules that are toxic to the body. Nonetheless, there is some preliminary evidence that when applied to the skin, it has anti-inflammatory properties and alleviates pain, such as that associated with RA.^14,15 DMSO appears to reduce pain by inhibiting the transmission of pain messages by nerves.¹⁶ It comes in different strengths and degrees of purity, and certain precautions must be taken when applying DMSO. For these reasons, DMSO should be used only under the supervision of a doctor.

DMSO applied to the affected area may reduce pain by inhibiting transmission of pain messages, and may also soften the abnormal connective tissue associated with disorders such as Dupuytren’s contracture, keloids, Peyronie’s disease, and scleroderma. Research on the use of topical DMSO to treat Dupuytren’s contracture remains preliminary and unproven.¹⁷

Oral supplementation with dimethyl sulfoxide (DMSO) reduced relapse rates for peptic ulcer significantly better than did placebo or the ulcer drug cimetidine (Tagamet) in one study.¹⁸ Previous research showed that DMSO in combination with cimetidine was more effective than cimetidine alone.¹⁹ These trials used 500 mg of DMSO taken four times per day. The authors of these trials believe the antioxidant activity of DMSO may have a protective effect. Oral supplementation with DMSO should not be attempted without the supervision of a doctor.