Sun exposure can lead to sun bumps, formally known as Polymorphous Light Eruption (PMLE). This condition manifests as an itchy rash appearing on the skin shortly after being exposed to sunlight. This article provides guidance on recognizing these rashes, managing symptoms, understanding when to seek professional help, and preventing future occurrences.
Identifying Sun Bumps
Sun bumps (PMLE) are characterized by a rash that emerges within hours or days following sun exposure. The rash includes small, raised, red bumps, clusters of blisters, or larger inflamed patches that feel itchy or burning. While PMLE can appear anywhere on the body exposed to sunlight, it often affects areas newly exposed to sun, such as the upper chest, arms, legs, and neck. The face is rarely affected.
This reaction is an abnormal immune response to UV radiation, leading to inflammation in the skin. Both UVA and UVB light can trigger PMLE, with UVA being the primary cause and able to penetrate glass. The rash usually subsides within about a week if further sun exposure is avoided.
Immediate Relief and At-Home Care
Several at-home measures can alleviate discomfort and promote healing. Applying cool compresses or taking cool baths provide relief from itching and burning. Soothing lotions such as aloe vera gel or calamine lotion also calm irritated skin.
For persistent itching, over-the-counter (OTC) anti-itch creams containing low-dose hydrocortisone (0.5% to 1%) can be applied to the affected areas. Oral antihistamines, such as cetirizine or fexofenadine, also reduce widespread itching.
Avoid scratching the rash, especially any blisters, to prevent infection and promote healing. Protecting affected skin from further sun exposure is crucial, as continued exposure can worsen the rash and prolong its duration.
Professional Treatments and When to Seek Help
While many sun bump cases resolve with home care, medical consultation is appropriate in some instances. Seek professional help if the rash is widespread, severely painful, accompanied by a fever, or if home remedies do not provide relief after about a week. A medical professional can confirm the diagnosis.
For more severe or persistent cases, a doctor can prescribe stronger topical corticosteroids to reduce inflammation and itching. For extensive or debilitating cases, a short course of oral corticosteroids, such as prednisone, can be prescribed.
Another treatment option for recurrent or severe PMLE is phototherapy, which involves controlled exposure to specific wavelengths of UV light to gradually desensitize the skin over time. This is administered in a clinical setting over several weeks, often in early spring, to prepare the skin for summer sun exposure.
Strategies for Prevention
Preventing sun bumps focuses on minimizing and managing sun exposure. Gradual sun exposure, often called ‘hardening the skin,’ involves slowly increasing sun time in spring to build tolerance before intense summer exposure.
Consistent use of broad-spectrum sunscreen is important. Choose a sunscreen with an SPF of 30 or higher that protects against both UVA and UVB rays. Apply generously 15 to 30 minutes before going outdoors and reapply every two hours, or more frequently after swimming or sweating.
Wearing protective clothing offers another layer of defense; opt for long-sleeved shirts, long pants, and wide-brimmed hats made from tightly woven fabrics or those with a UPF rating of 30 or higher. Darker colors and synthetic fibers like polyester offer greater UV protection. Avoiding direct sun exposure during peak hours (10 AM to 4 PM) reduces the risk of sun bumps.