In this study, we report on the efficacy of combination therapy of second-generation antihistamine antagonist, fexofenadine hydrochloride, and leukotriene receptor inhibitor, montelukast sodium, for the treatment of 15 prurigo nodularis or pemphigoid nodularis patients, in whom conventional therapy was ineffective. All patients received 10 mg montelukast once a day and 240 mg fexofenadine twice a day for 4 weeks in addition to other medications they had been taking. We assessed the manifestations of the lesions and itching intensity before and after the therapy, and we evaluated each patient as (i) markedly improved, (ii) improved, (iii) slightly improved, (iv) no change, (v) worse. Two patients (13.3%) were evaluated as markedly improved, and the lesions of one patient completely disappeared. Three patients (20.0%) were evaluated as improved, and six patients (40.0%) as slightly improved. Thus, 11 of 15 cases (73.3%) improved by combination therapy of fexofenadine and montelukast, in which nine cases (75.0%) of prurigo nodularis and two cases (66.7%) of pemphigoid nodularis were involved. No patients revealed any side effects. This study revealed that combination therapy of fexofenadine and montelukast was effective for some patients with conventional therapy-resistant prurigo nodularis and pemphigoid nodularis.