Successful treatment of solar urticaria with UVA1 hardening in three patients.

Solar urticaria (SU) is an uncommon photodermatosis that presents with sensitivity to ultraviolet (UV) or visible light which triggers urticarial lesions. Treatment of SU is a challenge and usually involves antihistamines and photoprotection as a first-line treatment. Phototherapy regimens are recommended if these first-line treatments fail to control the disease. Induction of tolerance by phototherapy (UV hardening) has been commonly described as a treatment modality. UVA1 has deeper penetration to the dermis than UVA or NB-UVB; its use in SU has not been previously reported. We present 3 patients with SU who were successfully treated with UVA1.