Dapsone proved to be an effective treatment in a patient who suffered from erythema elevatum diutinum. Serious neurological side effects, however, appeared. The basic mechanism appeared to be a distal axonal degeneration of the motor neurons. Sensory conduction studies were normal in five consecutive EMG examinations. A diagnosis of anemia perniciosa was also made but the blood values returned to normal after starting B12-vitamin therapy. Pernicious anemia seemed not to be an etiological factor in the polyneuropathy of our patient because we were not able to show any damage to the sensory axons.