Abstract: 【Abstract】 Solar urticaria （SU） is a rare photosensitive skin disorder induced by ultraviolet and/or visible light radiation. Its pathological mechanisms remain unclear, primarily involving the conversion of serum and/or dermal chromophores into photoallergens after absorbing specific action spectra, subsequently inducing mast cell activation and leading to clinical manifestations such as wheals, erythema, and occasionally angioedema. The pathogenesis of SU involves abnormal chromophores and IgE, with mast cells serving as the primary effector cells. Its occurrence and development are mediated by the IgE-FcεRⅠ signaling pathway, the signal transducer and activator of transcription 3 pathway, and the non-classical opsin pathway. Clinical management strategies for SU mainly include sun protection and light avoidance, antihistamines, biologics, and photohardening therapy. This article reviews advances in the pathogenesis and treatment of SU based on current research in China and other countries.

Key words: Urticaria, Solar urticaria, Ultraviolet, Visible light, Mast cell, IgE, Omalizumab