The side effects of therapy using an excimer laser tend to be minimal. Comparing to medications such as biologics and steroids, the excimer laser is far safer. However, some patients might experience mild side effects such as redness in light skin. As for people with dark skin, the effect might include purpleness. Some other possible side effects linked to the treatment are pigmentation changes, temporary pain, and blisters. So, you are strongly suggested to conduct this excimer laser treatment under the supervision of your doctor to minimize the risks.