Penicillamine is the drug of choice in Wilson's disease and a therapeutic alternative in rheumatoid arthritis. Autoimmune complications associated with penicillamine include cases resembling systemic lupus erythematosus and Goodpasture's syndrome. We report a case of diffuse pulmonary hemorrhage associated with prolonged penicillamine use in a patient with Wilson's disease with evidence of circulating immune complexes and complement activation, but without serologic or morphologic evidence of systemic lupus erythematosus, Goodpasture's syndrome or renal disease.