Efficacy and safety of 308 nm excimer light in combination with either topical Tazarotene gel 0.1% or topical betamethasone valerate ointment 0.1% in treatment of plaque psoriasis: a clinical and dermoscopic study

The excimer light at 308 nm is a common tool in dermatology for a variety of conditions. It works well for hard-to-treat psoriasis subtypes. Using topical corticosteroids is the cornerstone of treating psoriasis. The only topical retinoid that is currently prescribed to treat psoriasis is tazarotene; it lowers inflammation, epidermal hyperproliferation, and aberrant keratinocyte differentiation. Objectives were to assess the safety and effectiveness of 308 nm excimer light monotherapy versus its combination with either topical tazarotene gel 0.1% or betamethasone valerate ointment 0.1% for treatment of localized chronic plaque psoriasis. Thirty psoriasis vulgaris patients (a total of 90 lesions) were divided into 3 groups; group 1: received excimer light alone, group 2: received excimer light with topical tazarotene gel 0.1%, and group 3: received excimer light with topical betamethasone valerate ointment 0.1% for 12 weeks. Assessment was done by photographs, psoriasis severity (TES) score and dermoscopy. A markedly significant improvement in the baseline TES scores after 6 and 12 weeks of treatment was detected in all studied groups. Group 2 achieved a significant improvement after 6 weeks compared to the other 2 groups (p = 0.016). However, after 12 weeks of treatment, groups 2 and 3 achieved significant improvement in their TES scores compared to group 1 but with no significant difference in between (p = 0.229). We concluded that Excimer light combined with topical Tazarotene gel is an efficient and safe line of treatment for psoriasis. It works more effectively than either excimer light monotherapy or excimer light plus topical betamethasone valerate ointment.