Phototoxicity and photoallergy are two adverse effects associated with photochemical reactions in the skin. Phototoxicity is a non-immune mediated reaction that occurs when a chemical compound is activated by light, leading to damage in exposed tissues. Photoallergy is an immune-mediated response where the light-activated compound modifies proteins in the skin, triggering an allergic reaction. Both conditions are significant in the development and testing of skin care products and medications.
