Sunburn is not due to the heat of the sun, but rather to the ultraviolet (UV) radiation bombarding the cells in the deeper layers of the skin. Sunburns can occur on cloudy days and in the winter. Since we cannot feel the radiation, the symptoms appear only after the cells are damaged and become inflamed. A sunburn may not be apparent until after you have gotten out of the sun. The pain of sunburn also worsens over time, reaching a peak 12 to 48 hours later. Damaged skin later peels off, usually 2 to 7 days later.
Sunburn has long-term risks. Blistering sunburns, particularly in children, increase the risk of melanoma. Ongoing sun exposure, even without burning, leads to premature aging of the skin and skin cancer.
Skin is sunburned when it becomes red, warm, and painful after exposure to ultraviolet light from the sun or tanning booths. Moderate cases can lead to temporary disability, and severe cases can lead to swelling, blistering, fever, and dehydration.
Once the skin has burned, there is little that can be done other than providing comfort while the body heals itself. Therefore, prevention is the most important step to take. Use ample, frequently applied sunscreen with a broad-spectrum SPF 30 and above. When outdoors, wear sun-protective clothing, hats and sunglasses to protect the skin and eyes from harmful UV rays.
If you get a sunburn, taking a cool shower or bath, or placing cold, wet washcloths over the burn will help the symptoms. Over-the-counter medications like ibuprofen or aspirin may help (aspirin should not be given to children with a fever, or to those who are allergic). Avoid using products containing benzocaine or lidocaine, which can further damage the skin, or petrolatum (Vaseline), which can block pores.