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Sunburn: More than just red skin

In addition to being painful, sunburns are dangerous to your long-term health. When you're outdoors, it's important to protect your skin.

Hot, red, inflamed, painful skin—yes, sunburn is as bad as it looks and feels. Sunburn is a sign that your skin has sustained serious damage. This damage increases your risk for skin cancers and leads to long-term problems such as premature wrinkling, spotting and aging of the skin.

Luckily, sunburn is easily prevented.

What is sunburn?

You get sunburn when your skin is overexposed to the sun or another source of ultraviolet (UV) light, such as a sunlamp or a tanning bed.

Sunburn occurs when the amount of exposure to ultraviolet light exceeds the ability of the body's protective pigment—melanin—to protect the skin.

There is no safe form of UV light, according to the American Academy of Dermatology (AAD). UVB rays are the rays most likely to cause sunburn.

UV rays are most intense in the summer, at higher altitudes and closer to the equator. Reflections from water and snow can increase your chance of sunburn. Even on cloudy days, UV rays reach Earth and can cause sunburn.

Any change to your skin color caused by UV rays—including a suntan—is a sign of skin damage.

Short-term symptoms, long-term damage

UV rays can damage your skin in as little as 15 minutes. Sunburn symptoms generally occur four hours after your skin is exposed to UV rays. If you have light skin, you're likely to sunburn more quickly than a dark-skinned person.

Sunburn will cause reddening and swelling of the skin, as well as itching. The skin may peel within three to eight days of the sunburn.

A serious sunburn can cause fever, chills and headache. A severe sunburn may also blister.

According to AAD, you should seek medical attention if you have a sunburn that is severe or is accompanied by a fever.

While the short-term effects of sunburn can be painful and irritating, the long-term effects are far more significant.

Having many sunburns, especially during childhood, increases the likelihood of developing malignant melanoma—the most serious form of skin cancer, according to the National Cancer Institute.

Chronic exposure to the sun can also cause your skin to develop brown spots, wrinkle and sag. It can also increase your chance of developing other types of skin cancer, such as basal and squamous cell cancers.

Preventing sunburn

The best way to avoid sunburn is to protect yourself from the sun.

The AAD offers these recommendations:

  • Plan outdoor activities early or late in the day. The sun's rays are most intense between 10 a.m. and 2 p.m.
  • Wear a broad-brimmed hat and sunglasses.
  • Sit in the shade whenever possible.
  • Wear tightly woven, long-sleeved clothing.
  • Before going outside, apply a broad-spectrum sunscreen with a sun protection factor (SPF) of at least 30—even on cloudy days. Sunscreen should be reapplied about every two hours, or more often if you are swimming or perspiring.

You might also want to keep tabs on the UV index in your area. The index helps show how much UV reaches the Earth's surface. Sun protection is especially important when the index is high. Check your local index at epa.gov/sunwise/uvindex.html.

Treating a sunburn

If you do get sunburn, take a cool shower or bath, or place a cold washcloth on the burn. If your skin is not blistering, moisturizing cream may also relieve discomfort. With blisters, dry bandages or antibiotic cream may help prevent infection.

Over-the-counter medications like ibuprofen, aspirin or other nonsteroidal anti-inflammatory drugs may also help relieve sunburn pain, as can aloe-based creams or calamine lotion. Avoid products with petroleum (which traps heat) or benzocaine or lidocaine (which are local anesthetics that can irritate skin), the AAD says.

If you have questions about sunburn, talk to your doctor.

Reviewed 3/14/2024

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