Sun allergy is something that seems to be counterintuitive: how can we be allergic to sunlight if we need it and live on a planet that is always exposed to it? However strange it may be, some people react to sunlight, and those suffering from grave forms of sun allergy even have to stay indoors and never leave the house.Our climate is shaped by many factors, but sunlight is the decisive one: without the Sun, we would have frozen a long time ago. Human beings need sunlight to have their bodies function properly. It provides us with vitamin D, which is synthesized within us, but without the Sun these processes cannot be triggered. The Sun can influence our bodies in a number of ways – even by means of solar storms! For most people, sunbathing is an activity (if it fits the definition) that is loved by almost everyone, and even the view of sunrises and sunsets makes us feel calm, relaxed and inspired. However, there are people who cannot enjoy sunlight the way the majority of people do.
What is sun allergy?Another name for sun allergy is photosensitivity. A person suffers from sun allergy when their immune system considers sunlight to be a danger and reacts as if it should protect the body from the Sun’s influence. Actually, it’s not the sunlight itself that the body is trying to eliminate, but the cells in the skin that are affected by Sun rays.
Sun allergy symptomsThere are several types of photosensitivity, varying in symptoms and races affected.
- Polymorphous light eruption, which is often abbreviated as PMLE. It implies a reaction within two hours of exposure to sunlight, which results in a rash that is burning or itching. Among other symptoms of PMLE are headache, nausea, and chills, though these resolve within a couple of hours. The rash usually appears only on the skin exposed to sunlight, not the areas covered by clothes. In most cases, it disappears within a couple of days, if there is no more sun exposure.
- Hereditary PMLE, another name for which is actinic prurigo. This one is similar to common PMLE, but it is inherited and diagnosed in people who are American Indian or have such relatives. The symptoms characteristic of actinic prurigo are the same as in non-hereditary PMLE, but they are severe, and the condition manifests itself earlier. Besides, they are mostly around the lips or just on the face. In some climates, the symptoms can persist regardless of season.
- Photoallergic eruption is a reaction of the immune system to the chemicals, like sunscreen, cosmetics, etc., that are exposed to sunlight when applied, or ingested – even NSAIDs can trigger such a reaction. The symptoms are small blisters or an itchy rash. The red rash can appear even on the skin covered by clothing, and it usually takes a couple of days for the body to react. The symptoms disappear when you stop using the chemical that caused them.
- Solar urticaria is a rare condition that is more likely to affect young women. It causes large red bumps called hives, which appear on sunlight-exposed skin areas as fast as within several minutes. These hives disappear quickly, but they come back when you expose your skin to sunlight again.
Sun allergy preventionIt is impossible to prevent sun allergy if it is solar urticaria: the only way to avoid symptoms is to stay indoors living in dark rooms, which is depressing. As to other kinds of sun allergy, the following advice can help you keep your skin protected:
- If your skin is likely to be exposed to sunlight soon, apply a sunscreen with SPF of 15 or above, which protects against both A and B UV types.
- Avoid being outdoor in “peak hours”, i.e. from 10 am to 4 pm.
- Wear clothes that cover your legs, back and arms. Wear a hat to protect your head, and sunglasses.
- Be careful when choosing cosmetics and stop using the products that trigger reaction.
Sun Allergy (Photosensitivity) – Health.harvard.edu