DMSO is used topically to decrease pain and speed the healing of wounds, burns, and muscle and skeletal injuries. DMSO is also used topically to treat painful conditions such as headache, inflammation, osteoarthritis, rheumatoid arthritis, and severe facial pain called tic douloureux. It is used topically for eye conditions including cataracts, glaucoma, and problems with the retina; for foot conditions including bunions, calluses, and fungus on toenails; and for skin conditions including keloid scars and scleroderma. It is sometimes used topically to treat skin and tissue damage caused by chemotherapy when it leaks from the IV that is used to deliver it. DMSO is used either alone or in combination with a drug called idoxuridine to treat pain associated with shingles..