Photosensitivity, Solar Allergy and Photodermatosis

Generality

The potential risks associated with "excessive sun exposure are now overt and therefore photoprotection is always encouraged. However, many people are unaware of a phenomenon that can accelerate and aggravate sun damage to the skin; this condition, called photosensitivity. , consists of an "abnormal and excessive skin reactivity to" solar (or artificial) irradiation.

A photosensitive subject can thus experience a photodermatosis, that is a "skin disease (erythema, urticaria or sun allergy) that arises following a" mild or otherwise normally insufficient sun exposure to trigger these symptoms. The photosensitivity reactions are caused by the interaction of sunlight with some drugs taken by the patient or with particular predisposing medical conditions. These skin reactions can be induced by various causes: sun exposure is the determining factor for the onset of the picture. clinical and can be directly responsible for dermatosis (direct forms), or act indirectly, through the intervention of photosensitizing substances (mediated forms). The direct forms include a series of dermatological pathologies that are induced or worsened mainly by ultraviolet (UV) rays; a classic example is represented by vitiligo

The following article provides an overview of some of the medical conditions associated with photosensitivity.

Allergy and phototoxic reactions

Photodermatoses represent the clinical expression of an allergic or phototoxic reaction to the sun. These skin affections present themselves with different and easily identifiable manifestations, but the main characteristic, which unites them, is a high photosensitivity.