**4.4 Contraindications**

Photosensitive disorders Xeroderma pigmentosa SLE History of malignant melanoma

## **4.5 Side effects of excimer light treatment**

The treatment aims to induce visible erythema in the treated lesion (supraerythematous dose) but not cause a blister or second-degree burn. Too high a dose can lead to blister formation. Side effects may include painful erythema, desquamation, erosion, and reactivation of herpes infection.

Although long-term exposure to ultraviolet radiation ultimately causes skin aging and skin cancer, the risk of excimer light therapy is suggested to be less than that of narrowband UVB.
