Both photoallergy and phototoxia are sensitive reactions to light. They are produced by having taken a medicine that, in some way, reacts with sunlight and causes negative changes in the body.
These photosensitivity reactions are quite common. In addition, they do not occur only with medications, but can be caused by other agents such as cosmetics. The problem is that both tend to cause skin damage, such as redness or itching.
Despite this, both conditions have certain characteristics that differentiate them. It is important to know them, since each one is developed by a mechanism that determines the treatment to be applied. In this article we explain it.
What is photoallergy?
Photoallergy is an allergic reaction, that is, it is mediated by the immune system. It consists in that the body identifies a substance as foreign and triggers an immune reaction to fight against it.
It can be the compound of a medicine or a cosmetic that, when in contact with the UV rays of the sun, transforms and triggers the reaction. That is, the substance is first transformed by sunlight, and then the result is what causes the allergy.
There are many products in regular use that can cause this complication. However, photoallergy occurs only in those who have a sensitivity or predisposition to it.
For example, it can appear from certain deodorants, soaps, sun creams or even perfumes. Similarly, medications such as sulfonamides or anti-inflammatories can also trigger it.
What happens is that eczema-like lesions appear on the skin. That is, there is redness, itching, vesicles, and so on. But, unlike other allergies, the reaction occurs throughout the body, even in areas that have not been exposed to the sun.