Phototherapy has been one of the first and still frequently used treatments for psoriasis, which uses ultraviolet (UV) light to slow the growth of skin cells and reduce inflammation. Over the last few decades, however, phototherapy using lasers has grown in popularity.
Excimer lasers aim a high-intensity ultraviolet B (UVB) light dose of a highly specific wavelength – 308 nanometres – directly at the psoriasis plaques. Because the laser light is focussed on the affected area, it does not damage the surrounding skin and it reduces the risk of wider UV radiation exposure. The disadvantage of such a focussed therapy, is that it can only be used for relatively localised psoriasis, rather than larger areas of the body. It has also been shown to reduce lesions in areas that are harder to treat, including the knees, elbows, and scalp.
The Excimer laser can be used to treat mild-to-moderate psoriasis and patients usually have two sessions a week for 4 to 10 sessions to achieve optimal results. It is generally safe, but occasional side-effects include redness, purple-coloured spots, pigmentation and scarring.
Several studies have confirmed that Excimer laser treatment is safe, effective, and well-tolerated. In a 2020 study published in the Journal of Drugs and Dermatology, the Excimer laser was found to be fast, safe, and more effective than most other existing options for treating psoriasis, including topical medications and traditional forms of phototherapy1. Another 2020 study, showed that 92% of individuals reduced the severity of their psoriasis plaques by at least 75% after 5 to 7 weekly sessions with an Excimer laser when used at an optimal therapeutic dose2. Finally, a 2023 systematic review concluded that the Excimer laser has an established place in the treatment of plaque psoriasis as a first or second-line therapy in mild disease, or in combination with systemic treatments in moderate-to-severe disease3.
Comment
Excimer laser therapy has an established place in the treatment of mild-moderate psoriasis. It is not suitable in situations where large areas of skin are involved but is highly effective in the treatment of localised disease.
To learn more about phototherapy you can download or order from our shop our Psoriasis and Phototherapy leaflet.
References:
- Marchetti A, Bhutani T et al. Therapies for Psoriasis: Clinical and Economic Comparisons. J Drugs Dermatol 2020; 19: 1101-1108
- Thibodeaux Q, Beck K, et al. Treatment of Plaque Psoriasis with an Excimer Laser Utilizing an Optimal Therapeutic UVB Dose Protocol. J Drugs Dermatol 2020; 19: 349-354
- Heidemeyer K, Kulac M et al. Lasers for the treatment of psoriasis: a systematic review. Expert Rev Clin Immunol 2023; 19: 717-744