All of us have experienced a sunburn in the past, most likely in childhood. Even people who are careful with sun protection can forget to wear sunscreen on cloudy days, neglect to reapply after swimming, or miss those hard-to-reach spots.
What exactly is a sunburn at the cellular level? A sunburn is a first- or second-degree burn that is caused by ultraviolet radiation. Overexposure to sunlight starts a cascade of events in the skin, including dilation of blood vessels producing redness, release of inflammatory mediators that create swelling, and eventual death and elimination of the damaged skin cells. Clinically, the result is redness that begins about three to five hours after exposure and peaks at 24 hours, then subsequent peeling of the superficial layer of skin. If the sunburn is more severe, blistering may occur, indicating a second-degree burn involving the deeper dermal layer of skin. Blistering sunburns take longer to heal and can leave discoloration.
The treatment of sunburn is mostly directed at relief of the associated symptoms of redness, heat, pain, and swelling. Once the skin cells have been damaged, they are destined to slough off. There is little to do to reverse that process. If you do develop a sunburn, take the following steps:
- Get out of the sun right away and keep the affected area covered and protected from additional sun exposure as it heals.
- Try cool baths or soaks. Colloidal oatmeal baths with products such as Aveeno may be particularly soothing.
- Apply bland moisturizing creams to the sunburn daily. Ointments, although soothing, are occlusive and may make the skin feel even warmer.
- Drink water to prevent dehydration.
- Take an over-the-counter, non-steroidal anti-inflammatory drug (NSAID) such as ibuprofen (Motrin, Advil) or aspirin to reduce pain and swelling.
- Don’t pick! Peeling off blisters increases the risk of both infection and discoloration. Likewise, avoid loofahs or exfoliation. Instead, moisturize the skin and allow it to slough off naturally.
- If the skin becomes itchy as it peels, consider an over-the-counter oral antihistamine.
- Avoid topical products containing benzocaine or lidocaine for pain relief. They can cause a secondary allergic contact dermatitis in susceptible individuals.
- Although not specific for sunburn, over-the-counter topical 1% hydrocortisone cream may reduce the swelling and discomfort. Stronger topical steroid creams may be prescribed by your doctor.
- If you experience systemic symptoms such as chills and fever or have an extensive area of skin covered with blisters, such as an entire back, call your doctor. This is especially true for children.
Sunburns are best prevented in the first place. Repeated sunburns damage cellular DNA, which promotes premature aging, wrinkles, brown spots, precancerous actinic keratoses, and skin cancers including melanoma. Studies have shown that more than five blistering sunburns between the ages of 15 and 20 increase the risk of melanoma by as much as 80 percent.
It is intuitive that people most at risk for sunburn are those with fair skin, red to blonde hair, and blue eyes. Remember other risk factors that contribute to sunburn, such as:
- Medications: Common medications—including antibiotics (doxycycline, Bactrim, ciprofloxacin), blood pressure medicines (HCTZ), and retinoids—can increase sun sensitivity.
- Reflection: Highly reflective surfaces such as water and snow increase exposure to the sun’s rays. Shade only protects against direct sunlight. If seated under an umbrella at the beach, 20 percent of sunlight is still reflected from the sand. On a boat, 10 percent is reflected from the water, and an additional 10 percent from the boat itself. Fresh snow reflects up to 90 percent of ultraviolet radiation.
- Cloud coverage: Be careful on cloudy days! Cloud coverage is not necessarily protective and may actually enhance UV radiation due to scattering of light.
- Latitude: UV levels increase closer to the equator.
- Altitude: UV radiation increases 4 percent for every 1,000-foot increase in elevation. Denver, at 5,280 feet (“Mile High City”), has 20 percent higher UV radiation than at sea level.
Practice good sun habits. Protect yourself from both the acute and long-term consequences of sunburn. Avoid peak midday hours; wear sun-protective clothing, hats, and sunglasses; and regularly apply broad-spectrum sunscreens with an SPF greater than 30, such as EltaMD UV Clear or the more water-resistant EltaMD UV Sport.