Can You Be Allergic to the Sun? (2024)

You can be allergic to the sun. A sun allergy—sometimes also called photosensitivity—occurs when the skin is hypersensitive to ultraviolet (UV) rays, which the sun naturally emits. Signs of sun allergy can include an itchy, painful, blistering, or peeling rash. This reaction can occur within minutes or hours of sun exposure and can vary in intensity from mild discomfort to severe skin irritation.

Genetics, certain medications, and underlying autoimmune conditions can cause sun allergies. Treatments for sun allergies range from lifestyle modifications to medications, depending on the severity and type of sun allergy. Researchers aren’t sure how many people sun allergies affect, but an estimated 2% to 18% of people worldwide may live with a sun allergy.

There are different types of sun allergies, each with its different causes, triggers, and symptoms. The four main types of sun allergy include:

• Polymorphous light eruption (PMLE): PMLE is the most common type of sun allergy, mainly affecting people with dark skin. Within hours of sunlight exposure, an itchy or burning rash with red bumps or blisters develops, lasting from several days to two weeks. PMLE typically occurs in spring or early summer, as the skin is less acclimated to sunlight after winter.
• Solar urticaria: This is a rare form of sun allergy that causes hives (raised, itchy welts) that appear on the skin within minutes of sun exposure and typically go away within 24 hours. Solar urticaria often occurs due to an abnormal immune response to UV rays.
• Photoallergic reaction: This type of sun allergy occurs when ingredients in certain medications interact with UV rays, causing the immune system to overreact. As a result, you can develop a rash with red bumps or oozing blisters. The rash typically develops within one to three days after sun exposure.
• Actinic prurigo: Actinic prurigo is a rare inherited sun allergy that causes itchy, bumpy, or scaly skin lesions after sun exposure. This chronic condition often begins in childhood before age 10.

Symptoms

Sun allergy symptoms can vary from person to person, depending on the severity and type of sun allergy they have. While some people may have only mild symptoms, others may develop more severe reactions to sunlight exposure.

Polymorphous Light Eruption (PMLE) Symptoms

PMLE symptoms usually develop within hours to four days after sun exposure, and you may experience:

• Itchy or burning rash
• Redness or scaling of the skin
• Small, red bumps or blisters on sun-exposed skin
  

Solar Urticaria Symptoms

Symptoms of solar urticaria often develop within minutes of sun exposure and may include:

• Hives (raised, itchy welts) on sun-exposed skin
• Itching or burning sensation on the affected skin
• Redness and swelling in the exposed areas
  

Photoallergic Reaction Symptoms

Medications and certain cosmetic products may cause a photoallergic reaction to the sun. As a result, you might experience the following symptoms within hours or days of sunlight exposure:

• Itchy rash or red blisters that develop on sun-exposed skin
  
• A rash that spreads beyond sun-exposed areas
• Swelling and tenderness on the affected skin
  

Actinic Prurigo Symptoms

With actinic prurigo, symptoms usually appear shortly after sun exposure and resolve within a few days. Additional sun exposure can re-trigger the allergic reaction to sunlight and cause a recurrence of symptoms, including:

• Bumpy or scaly patches on sun-exposed skin
• Burning or itching sensations
• Red bumps, hives, or small blisters

Sun allergies occur when the skin has a hypersensitive reaction to sunlight or artificial ultraviolet (UV) rays such as tanning beds. When you have a sun allergy and spend time in sunlight, your immune system perceives UV rays as a threat.

As a result, the immune system produces and releases inflammatory chemicals (e.g., histamines) to protect the body. The release of histamines and other immune system cells leads to skin inflammation, rash, and other sun allergy symptoms.

The following causes and risk factors can increase your likelihood of developing sun allergy symptoms:

• Polymorphous light eruption:Research suggests an abnormal immune reaction to UV light causes PMLE. A history of other skin conditions, a family history of PMLE, and living in northern climates are risk factors for developing PMLE.
• Solar urticaria:What exactly triggers the immune response to sunlight or UV rays with solar urticaria is unknown. A family history of sun allergies and a previous history of other allergic conditions can increase the risk of solar urticaria.
• Photoallergic reaction:Certain medications and cosmetics are linked to allergic reactions after exposure to sunlight. Substances in certain medications (e.g., antibiotics, antihistamines, nonsteroidal anti-inflammatory drugs) and cosmetics (e.g., benzoyl peroxide or retinol) can sometimes trigger an immune response, which leads to skin inflammation and rash.
• Actinic prurigo:This is an inherited (genetic) sun allergy that predominantly affects people with indigenous ancestry in North, Central, and South America. A family history of actinic prurigo increases the risk of developing it.
  

Diagnosis

To diagnose a sun allergy, a healthcare provider will thoroughly review your personal and family medical history, ask about your symptoms (such as when they developed and how long they lasted), and perform a physical examination.

The provider will generally try to rule out other possible causes of your symptoms. They may evaluate your symptoms using one or more of the following tests:

• Phototesting:This involves exposing small areas of the skin to controlled amounts of UV light to observe any allergic reactions. This test helps determine the specific wavelength of light (UVA or UVB) that triggers an allergic reaction.
• Patch testing:This helps identify photoallergic reactions. A provider will apply small amounts of potential allergens (e.g., medications or certain substances found in cosmetics) to patches and place them on the skin. The provider will then expose the patches to UV rays and ask you to return to the office later so they can examine your skin to look for allergic responses to the substances they placed on the patches.
• Blood tests:This uses a sample of your blood, which a healthcare provider will send to a lab to rule out other conditions that can cause sun sensitivity, such as lupus.
• Skin biopsy:Takes a small sample of your skin, which a provider sends to a pathologist—a physician who specializes in diagnosing disorders by looking at biopsy specimens—to examine under a microscope. This helps them rule out other skin conditions, such as cancer, that may produce similar symptoms to a sun allergy.

While there is no cure for most sun allergies, treatments can help relieve symptoms, reduce the frequency of allergic reactions, and improve your quality of life. Treatment options vary based on the specific type of sun allergy and the severity of symptoms. A provider can recommend a combination of lifestyle changes, medications, and therapies.

Lifestyle Changes

Making adjustments to your lifestyle may help manage a sun allergy. This may include:

• Avoiding direct sunlight during peak hours of the day (usually between 10 AM to 4 PM)
• Wearing protective clothing, such as wide-brimmed hats, long sleeves, and UV-blocking sunglasses
• Applying a broad-spectrum sunscreen with a high sun protection factor (SPF) to exposed skin
• Identifying and avoiding specific substances (medications or cosmetics) that trigger the allergic response in combination with sunlight

Topical Medications

For mild sun allergies, a provider may recommend over-the-counter hydrocortisone creams or ointments that you can apply directly to the skin. These topical medications can help relieve itching and inflammation after an allergic reaction. In some cases, the provider may opt to prescribe stronger corticosteroid creams for more severe reactions.

Oral Medications

A healthcare provider may prescribe oral medications (taken by mouth) for severe sun allergies to help you manage symptoms and prevent future allergic reactions. These medications may include:

• Antihistamines to reduce itching and allergic reactions
• Nonsteroidal anti-inflammatory drugs (NSAIDs) to help relieve pain and inflammation
• Monoclonal antibodies, which block the body’s response to sunlight to reduce allergic reactions
  

Phototherapy (Light Therapy)

Light therapy involves controlled, gradual exposure to UV light that may help desensitize skin to sun exposure and reduce reactions to sunlight. Phototherapy is a common treatment approach for PMLE.

How to Prevent a Sun Allergy

While there is no surefire way to prevent most sun allergies, there are several things you can do to help reduce the frequency and severity of allergic reactions to sunlight, such as:

• Applying a broad-spectrum sunscreen with a high SPF before sun exposure
• Being cautious about the medications or cosmetics you're using, as some can increase your sensitivity to the sun
• Reapplying sunscreen throughout the day, especially if you are swimming or exercising outside
• Seeking shade during peak sunlight hours
• Staying inside on hot days
  
• Wearing protective clothing, sunglasses, and hats when outdoors
  

Certain conditions may increase your risk of developing a sun allergy. These include:

• Atopic dermatitis (eczema):A chronic skin condition that causes itchy and inflamed skin. While sun exposure may help clear eczema in some people, research shows that some may experience worsened symptoms after sunlight exposure.
• Psoriasis:A chronic skin condition that produces a rapid buildup of skin cells, leading to red, scaly patches that can be itchy and painful. While psoriasis is not directly related to sun allergies, some people with psoriasis may experience worsened symptoms when they have sun exposure.
• Systemic lupus erythematosus (SLE or lupus):This is an autoimmune disease that affects various body systems, including the skin. Some people with lupus may experience photosensitivity, where exposure to sunlight can trigger skin rashes and worsen the disease.
  

Living With a Sun Allergy

Living with a sun allergy can profoundly affect your life, from everything between work to leisure activities with friends and family. While living with a sun allergy can be challenging, embracing lifestyle adjustments and taking your medications (if any) as prescribed can help you manage your symptoms, spend time outdoors, and lead a fulfilling life.