Thalidomide is now approved for the treatment of multiple myeloma and erythema nodosum leprorum. It has also been tested, with beneficial effects, in a variety of inflammatory diseases, especially those involving the skin and mucous membranes: recurrent aphthous stomatitis, oral and oesophageal ulcers in HIV, oral and genital ulcers and intestinal symptoms in Behcet's syndrome, graft versus host disease, skin manifestations in systemic lupus erythematosus, sarcoidosis, and tuberculosis. In these diseases, especially in those cases resistant to conventional treatments, thalidomide seems to have a promising role as a secondary therapeutic option.