Silpa-archa N, Pattanaprichakul P, Charoenpipatsin N, et al. - In this open study involving 12 patients [mean age was 41.3 years (range: 25-71)], researchers tested the safety and effectiveness of ultraviolet A1 (UVA1) phototherapy in psoriasis by evaluating the clinical and histological results. Participants in the study were patients with moderate to severe plaque-type psoriasis. At baseline, Psoriasis Area and Severity Index (PASI) scores were determined at sessions 10th, 20th and 30th and 1 month following treatment. Data reported that the median PASI scores at baseline, session 30th, and 1-month post-treatment, respectively, were 16, 11 and 9.2. The phototherapy was well tolerated by all patients and the most common side effect was skin tanning. While medium-dose UVA1 phototherapy showed some effectiveness in moderate to severe plaque-type psoriasis. However, it may not be a great option.