Fotoallergiassa

Fotoallergiassa, also known as photoallergy or light allergy, is a condition where the skin reacts adversely to ultraviolet (UV) radiation. This reaction is an immune system response, distinct from photodermatitis or photoirritation, which are non-immune mediated skin reactions to light. Photoallergy typically develops after exposure to a photosensitizing agent, which can be a medication, a cosmetic ingredient, or a substance applied topically. When this agent is exposed to UV light, it undergoes a chemical change that triggers an allergic reaction in the skin.

The symptoms of fotoallergiassa usually appear 24 to 48 hours after exposure to the photosensitizing agent and sunlight. They can include itching, redness, swelling, and the development of eczema-like lesions or small blisters. The rash often appears in areas of the skin that have been exposed to sunlight. Unlike photoirritation, which can occur in anyone exposed to sufficient amounts of the causative agent and light, photoallergy is a true allergic reaction and may occur even with low levels of exposure in sensitized individuals.

Diagnosis involves a thorough medical history, including a review of medications and products used, followed by a physical examination of the affected skin. Patch testing and photopatch testing are crucial diagnostic tools. Photopatch testing involves applying potential photosensitizing agents to the skin and then exposing the area to UV light to see if a reaction occurs.

Treatment focuses on avoiding the causative agent and protecting the skin from sunlight. Sunscreens that block UVA and UVB radiation are essential. Topical corticosteroids may be prescribed to manage inflammation and itching. In severe cases, oral corticosteroids might be necessary. Prevention is key, and individuals with a history of fotoallergiassa should be vigilant about checking product ingredients and informing their healthcare providers about their condition.