Sun allergies can be very uncomfortable, and they can definitely affect the quality of life for some patients. Sun allergies can happen after 30 minutes of being in the sun, or they can happen over time. So, what are the signs of a sun allergy, the causes, and how can you prevent them?
Sun allergies can also be called “polymorphous light eruption.” A sun allergy can present as little fluid-filled blisters and swollen plaques. It can include redness, stinging, flushing, blisters, and hives.
Symptoms can range from slightly uncomfortable to painful. And for some patients, sun allergies have even been known to bring on flu-like symptoms.
Sun allergies are not autoimmune diseases (when the immune system overreacts and attacks tissue), but they can look like autoimmune diseases. Sun allergies can also be a symptom of autoimmune diseases.
For instance, even a few minutes of exposure to UV radiation can cause rosacea-prone skin to have intense redness and flushing. For this reason, it’s important to get a diagnosis from a dermatologist. That way, you can truly identify the rash and whether it’s a symptom of an autoimmune disease.
Sun allergies occur on areas of the skin that are exposed to the sun, and sometimes the reaction can happen over time. Maybe even days later you might notice irritation on your chest, hand, or the backs of your legs.
Sun allergies mostly affect women, especially women between the ages of 20 and 50. However, it can also happen to men.
What causes sun allergy?
Sun allergies can happen when an area that’s normally covered up gets exposed to the sun. This scenario is common during season transitions from cold to warm. You may notice the rash 30 minutes or days later.
Most sun allergies are normally brought on by UVA radiation. UVA radiation penetrates all the way to the middle layer of your skin and can cause significant irritation. On the other hand, UVB can also cause sun allergy in photosensitive individuals, but it's much more likely to cause sunburn, which is an actual radiation burn, not an allergic reaction.
Exposure to visible light can also cause sun allergies. However, sun allergies do not truly mean you’re allergic to the sun. Exposure to visible light increases specific antigen levels in our skin, it can cause the skin to have an allergic reaction to those antigens. “Antigens are usually proteins or sugars (polysaccharides) found on the outside of things like cells or viruses” (Mayo Clinic).
This is another reason why it’s super important to wear a broad-spectrum and physical sunscreen (mineral zinc oxide and titanium dioxide filters), one that protects the skin from UVB, UVA, and visible light. Chemical sunscreens (avobenzone and oxybenzone filters) do not protect against visible light.
Visible light can actually suppress the skin’s immune system. When the immune system is suppressed, its ability to rid the body of pre-cancerous cells decreases. It’s interesting to note though that many people with sun allergies have been known not to have this suppressive reaction to UV light.
What treats sun allergy?
Always wear clothes that cover your skin. You can even wear UPF clothing, which is clothing that has UV radiation protection. Make sure you also wear a hat that covers the back of the neck.
Sun allergies often calm down on their own after your sun gets used to the sun exposure, but your dermatologist might recommend topical steroids to reduce the itching and redness.
Phototherapy can also be used to make the skin more resilient and to help the skin suppress its response to specific antigens. However, phototherapy is not always the best course of action for some photosensitive patients.
Most importantly, remember to wear a physical, broad-spectrum sunscreen (mineral zinc oxide and titanium dioxide filters). Preferably, wear one that is SPF 50, PA++++, and water-resistant. Remember to apply every two hours and to reduce your exposure to the sun. This includes sitting near windows because UVA radiation can also penetrate the skin through windows.
Photocred: 123RF