What is Sun Allergy: Symptoms, Causes, Treatment

Sun allergy is a type of allergic reaction that occurs when individuals with sensitive skin are exposed to sunlight for extended periods. It can manifest as redness, irritation, skin rashes, and swelling. In some individuals, sun allergy may be genetic, while in others, it can develop due to heightened sensitivity after exposure to other allergens. When the skin is exposed to the sun without protection for long periods, sunburns can occur. Many people confuse sunburns with sun allergies. Sunburns result from excessive exposure to ultraviolet (UV) light. Sunburns can occur due to prolonged natural sun exposure or from artificial tanning devices, such as tanning beds. Sunburn symptoms typically include redness, pain, and blisters, and they may appear 10–30 hours after exposure. These symptoms can generally be treated with medications and may take several days to fully resolve. In contrast, sun allergies can manifest symptoms within 5-10 minutes of exposure, although in some cases, this can take a few days.

What are the Symptoms of Sun Allergy?

Sun allergy typically affects areas of the skin that come into contact with the sun, but in some cases, symptoms may also appear on other parts of the body. The symptoms of sun allergy include:

Itching and redness
Irritation and discharge
Nodules, blisters on the skin surface, and urticaria (hives)
Stinging and burning sensations
Pain and swelling

In rare cases, sun allergy may also cause the following symptoms:

Moderate to severe headaches
Life-threatening anaphylaxis reactions
Dizziness
Fainting and loss of consciousness
Nausea and vomiting
Shortness of breath and respiratory blockage

What Causes Sun Allergy?

The onset of symptoms caused by sun allergy can vary from person to person. While some individuals experience symptoms within minutes, others may see them appear hours or even days later.

The exact cause of sun allergies has not been determined. Many scientists suggest that genetic predisposition may lead to sun allergies. Some scientists believe that proteins like histamine may trigger various immune responses when exposed to sunlight. Based on this, it can be said that the cause of sun allergies may vary from person to person.

The duration of sun exposure, the area of skin exposed to the sun, and the intensity of sunlight are direct factors that can influence the occurrence of sun allergy.

Certain medications can cause sun sensitivity and lead to allergies. These medications include antibiotics, chemotherapy drugs, cardiac medications, diuretics, and diabetes drugs.

Types of Sun Allergies

There are several types of sun allergies. These types differ based on the type of rash and its cause.

Sun Urticaria: This is the rarest form of sun allergy. Even brief sun exposure can cause severe redness, heat rash, swelling, irritation, and hives (urticaria).
Actinic Keratosis: This type of sun allergy is thought to be hereditary. Areas exposed to the sun, as well as areas that are not, may be affected. It is more common in individuals with darker skin tones. It is commonly known as "age spots" and generally develops in areas of the skin that have been exposed to the sun for long periods.
Photoallergic Reaction: Many chemicals are used in cosmetics and dermocosmetics. This type of allergy occurs when one of these chemicals reacts with sunlight. The chemicals can include sunscreen, serums, makeup products, medications, or perfumes. The onset of symptoms can vary from person to person and may appear within hours or days.
Polymorphic Light Eruption (PMLE): This is the most common type of sun allergy. Symptoms can appear a few hours after sun exposure and may include red swelling, rashes, and blisters. It is more commonly seen in individuals with fair skin, adults, and women.

How is Sun Allergy Diagnosed?

If sun allergy is suspected, individuals should consult a primary healthcare provider or dermatologist. Your healthcare provider will:

Evaluate your symptoms,
Review any chemicals and medications you are using,
Attempt to identify the triggering factors through various light tests and patch tests,
If these methods are insufficient, a biopsy of the skin surface may be taken for microscopic examination.

Diagnostic methods for sun allergies should be performed by expert dermatologists, and advanced tests may be conducted when necessary. The diagnostic methods are as follows:

Blood Tests: Used to determine allergy levels.
Phototest (UV Light Test): A test to observe the skin’s reaction to ultraviolet light in different wavelengths.
Patch Test: As the name suggests, substances believed to trigger the allergy are applied to the skin with a patch and left for one day. The skin is then exposed to ultraviolet rays from artificial sunlamps, and the reactions are observed.
Skin Biopsy: If the above tests are insufficient, this method may be used by expert dermatologists. It is usually done in a sterile environment under professional supervision. It is also used to determine if the allergy is due to another underlying metabolic disorder.

How Does Sun Allergy Go Away?

The first rule in treating sun allergy is, of course, avoiding sun exposure. For those who cannot sufficiently protect themselves from the sun or in more severe cases, phototherapy, antihistamine use, montelukast, corticosteroid use, and anti-itch creams can help.

How to Prevent Sun Allergy?

Individuals with sun allergies should take precautions to minimize their sun exposure. Here are some of the necessary measures:

Use of Sunscreen: This is important for everyone, not just those with sun allergies, especially during the summer. A broad-spectrum sunscreen with at least 50 SPF should be used. The sunscreen should be applied in a layer of 2 mg per square centimeter. This amount is sufficient for the face and is approximately equivalent to ⅓ of a teaspoon. For daily use, you can apply sunscreen along the length of your index and middle fingers. Sunscreen should be reapplied every 2 hours. However, in the case of sweating or swimming, sunscreen should be reapplied before the 2-hour mark.
Avoid Sun Exposure: It is important to avoid direct sun exposure, particularly during certain hours of the day. These hours are between 10:00 AM and 3:00 PM.
Wear Sunglasses
Wear Protective Clothing Against the Sun
Avoid Allergen Substances
Avoid Using Medications and Chemicals That Increase Sensitivity to Light

Sun Allergy in Children and Babies

Vitamin D is very important for the development of babies, and sunlight is needed to activate this vitamin. Babies and children have much more sensitive skin than adults. All the symptoms of sun allergies seen in adults can also be observed in babies and children. The precautions to be taken are similar as well. Children and babies should avoid direct sun exposure between 10:00 AM and 3:00 PM. Sunscreen should be applied generously to areas exposed to the sun, just like adults, and should be reapplied every 2 hours.

Babies should not be exposed to the sun for long periods all at once. The time spent in the sun should be gradually increased to help them acclimate.

Especially in babies with dermatitis, sun exposure can cause more severe reactions, so when outside, protective clothing, hats, and fragrance-free sunscreens should be used.

If you suspect sun allergy, don't forget to consult with our expert dermatologists and visit our page for the most reliable information regarding your health.

Last Updated Date: 10 August 2023

Publication Date: 10 August 2023

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