Nail psoriasis is estimated to affect 80–90% of psoriatic patients at some point in their lives (1). Psoriatic patients with more severe nail disease tend to have a worse skin condition, a higher rate of unremitting and progressive arthritis, and more associated anxiety and depression (2, 3). In addition, nail psoriasis may considerably impair manual dexterity and foot biomechanics.However, ma-nagement of nail psoriasis is often overlooked.The most practicable management of nail psoriasis involves the use of topical vitamin D analogues and corticosteroids (1, 4), usually applied twice daily. Alternative treatments, such as topical 5-fluorouracil, tazarotene, and systemic acitretin, cyclosporine, and infliximab, have also been reported with some success (5–9). Compared with calcipotriol monotherapy, com-bination therapy using calcipotriol on weekdays and clobetasol on weekends provided better control of nail psoriasis (10). In plaque psoriasis, Guenther et al. (11) demonstrated that even once-daily combination therapy sufficed. The purpose of the present study was to com-pare the efficacy and safety of once-daily calcipotriol combination therapy with betamethasone dipropionate and twice-daily calcipotriol monotherapy in the treat-ment of nail psoriasis. SUBJECTS AND METHODS