Dimethyl Sulfoxide; see MSM

Origin: A colorless, sulfur-containing organic by-product of wood pulp processing.

Dosage: Cream, gel; topically, 25 percent DMSO solution; take internally, only if prescribed by a physician.

Claims: Relieves pain and inflammation, improves joint mobility in osteoarthritis, rheumatoid arthritis, JRA and scleroderma, and manages amyloidosis (excessive build-up of protein in organs as seen in RA). Increases blood flow to skin.

What we know: Topically, appears to be an anti-inflammatory.

Studies: Controlled studies as a topical application for DMSO and OA have yielded conflicting results. Few human studies.

 Side effects of DMSO taken internally include headache, dizziness, drowsiness, nausea, vomiting, diarrhea, constipation and anorexia. Topical DMSO also can cause skin irritation and dermatitis. Do not use DMSO if you have diabetes, asthma or liver, kidney or heart conditions. Never take industrial-grade DMSO. Wash off any lotions or skin products before applying DMSO.