Sun allergy symptoms can appear in the form of a red rash that is extremely itchy and may develop small bumps that resemble hives.
Though a right amount of sunlight exposure to the skin is crucial, excess exposure may cause sun allergy or rashes, which usually develop within a few minutes to hours after spending time in the sun.
Sunburn rashes and skin allergies are quite common, with too much exposure resulting in:
These symptoms range from mild to severe and can lead to extreme complications.
Despite a variety of skin manifestations, there are two main types of rashes caused by sun allergies, which are:
- Polymorphous light eruption (PMLE)
- This rash looks like many mosquito bites and is most intense when the weather starts getting sunnier.
- It is very itchy and uncomfortable.
- Symptoms may range from:
- Small red dots to clear fluid-filled dots (vesicles)
- Eczema-like dry patches
- Large plaques or papules
- Target-like lesions
- In some cases, PMLE may appear in areas that are otherwise not exposed to the sun, like the chest.
- The commonly involved areas include the face, neck, arms and hands because they have direct sun exposure.
- In children, it starts as dry patches on the face with small red dots and severe itching.
- Lesions disappear in one to two weeks spontaneously if no further sun exposure.
- These bumps may be treated with a steroid cream, but the best way to stay rash-free is to use sun protection.
- Solar urticaria or hives
- This is less common than PMLE but can be more serious.
- This rash is characterized by itching and redness that usually occurs after about thirty minutes or less of sun exposure. However, the skin may return to normal after several hours.
- The condition can cause an anaphylactic reaction in severe cases.
- People who experience mild solar urticaria can avoid a reaction by using sun protection, but those with severe reactions should stay indoors when it’s sunny.
What causes sun allergy?
Allergic reactions to sunlight happen mainly because of excessive exposure to ultraviolet lights, ultraviolet A (UVA) and to some extent also ultraviolet B (UVB) light, which penetrates and damages skin cells.
The exact cause of these triggers is not fully known, but research suggests that it may be due to an inherited genetic disposition that runs in the family.
- The skin reacts to sunlight with an immune response, usually redness and infection.
- The occurrence of sun rash can be exacerbated by certain ingredients in skincare products (especially retinol and vitamin C serums) as well as certain medications that increase photosensitivity and skin sensitivity in general.
- The potential culprit medications include some antibiotics, chemotherapy medication, blood pressure medications and (sometimes) hormonal contraceptives. Always check for information about photosensitivity in the instructions.
Sun allergy manifests as skin redness, itchy rash or festering blisters on the back, shoulders, arms, chest and tops of the feet. Even though it mostly affects women between 20 and 40 years of age with pale or sensitive skin, it can happen to anyone regardless of age or gender. Depending on the intensity of sunlight and other factors, skin reactions can vary.
How can I prevent sun allergy rashes?
The skin can sometimes react to the ultraviolet A (UVA) and ultraviolet B (UVB) rays with itching, redness or blisters. The following tips will help prevent the onset of a sun allergy:
- Accustom the skin to sunlight slowly by avoiding long sunbathing sessions and the midday sun between 11 a.m. and 3 p.m.
- Use a sunscreen product (free of grease, fragrance and emulsifiers) with a high sun protection factor (SPF).
- Clothing provides only limited protection against UVA and UVB rays, but the darker and denser the fabric, the better.
We have a false sense of security in the shade since the environment reflects sunlight even in places appearing to be shady. Up to 70 percent of radiation intensity is reflected by sand, water, snow or buildings. Glass windows also don’t protect the skin from ultraviolet rays.
What are the treatment options for sun allergy rashes?
There is no cure or treatment to get rid of sun allergies. However, symptoms can be prevented or reduced by careful sun protection.
A few treatment options include:
- Use sunscreen with a physical blocker, such as zinc oxide or titanium dioxide. Reapply sunscreen each time after getting out of the water or drying off with a towel and every hour if sweating.
- Intense cases may require steroid therapy. A dermatologist might prescribe corticosteroid creams. If the skin reacts severely to the sun, the doctor might prescribe a dose of corticosteroid pills.
- The doctor may additionally advise on the use of vinegar compresses and antihistamines in case of painful itchy rashes.
- People who are suffering from sun allergies may need a diet that includes foods or supplements that are rich in calcium, selenium, zinc and beta-carotene.
- Aloe vera gel and coconut oil can sometimes serve as alternatives. Make sure the skin can tolerate these by doing a patch test on a small area behind the ears.
- Use an anti-itch cream to protect the skin. If itching worsens, the doctor may prescribe an antibiotic.
- Take pain relievers if necessary or if the pain persists.
Medically Reviewed on 8/2/2021
Healthdirect. Summer Skin Rashes. https://www.healthdirect.gov.au/summer-skin-rashes