Chlorothiazide‐induced photoaggravation of psoriatic lesion during narrowband ultraviolet B treatment in a case of psoriasis vulgaris

Dear Editor, Ultraviolet (UV) irradiation is a standard treatment for psoriasis; however, it leads to exacerbation of psoriasis in some patients. Here, we report a patient with psoriasis vulgaris, who developed aggravation of psoriatic lesions after a single irradiation of narrowband UV-B (NB-UVB). A-76-year-old Japanese woman presented with plaque-type psoriasis, which was diagnosed at the age of 10 years (Fig. 1a). Her psoriatic