Dermatitis herpetiformis that is unable to be controlled using dapsone and a gluten-free diet presents a therapeutic challenge. Three cases that responded well to sulfasalazine are presented. Two cases, who were unable to tolerate dapsone, had a rapid response to sulfasalazine, without apparent side-effects. The third case with dapsone-responsive blistering dermatoses, presumed to be dermatitis herpetiformis on the basis of serology, showed an excellent clinical response to sulfasalazine, but after 6 weeks of therapy had to cease it because of side-effects. Sulfasalazine is metabolized variably to sulfapyridine, a sulphonamide known to be an effective therapy for dermatitis herpetiformis but no longer available. Sulfasalazine should be considered as a management option for dermatitis herpetiformis.