October 19, 2017
Sunburned at the beach

Sunburn: Causes and Treatments

by Berkeley Wellness  |  

Sunburn is an inflammation of the skin caused by overexposure to the ultraviolet (UV) rays of the sun—in particular UVB, or ultraviolet B, radiation. UVA, or ultraviolet A, penetrates more deeply than UVB but is less likely to cause an immediate burn. Rather, it causes wrinkling and leathering, damages connective tissue, and may be crucial in the development of melanoma, the most deadly of skin cancers.

Sunburn is not only painful—it also speeds up the aging of your skin and significantly increases your chances of developing skin cancer. If you have fair skin, blue eyes, or red hair, you’re at greatest risk for sunburn, but even if you have a dark complexion, you need to be careful in the sun. Most sunburns are first-degree burns, but extreme overexposure—especially if you are fair-skinned—can result in second- or even third-degree burns.

Symptoms of sunburn

First-degree: reddish skin that feels hot and tender.

Second-degree: small, fluid-filled blisters that may itch and eventually break.

Third-degree: severely red to purplish skin discoloration, blistered skin accompanied by chills, mild fever, nausea, headache, or dehydration.

Note: A sunburn becomes most evident 3 to 6 hours after sunning, reaching a peak at 12 to 24 hours.

What causes sunburn?

Exposure to UVB causes several changes in the skin, including blood vessel dilation (widening), the release of inflammatory chemicals by skin cells, and the cells’ swelling and leaking fluid. These changes result in the characteristic redness and, when the cells swell and leak, blistering.

Using the UV Index

The UV Index indicates the amount of UV radiation reaching earth at noontime. The higher the index number, the greater your exposure when you go outdoors.

What if you do nothing?

Although very painful, a sunburn eventually heals as the skin renews itself, generally taking from one to four days for a first-degree burn that reddens the upper skin layer (epidermis), to four to seven days for a more severe second-degree burn that affects underlying layers.

Home remedies for sunburn

Virtually everyone is susceptible to some degree of skin damage from the sun’s rays given sufficient exposure. If you inadvertently get burned by the sun, the following tips will help minimize any pain and swelling.

  • Soak the affected area for 15 minutes in cold water (but not ice water), or apply cold compresses. This provides some immediate relief from the pain, conducts heat away from your skin, and reduces swelling.
  • Get some pain relief. If your sunburn is very painful, take an over-the-counter pain reliever such as aspirin, ibuprofen, or acetaminophen. Aspirin and ibuprofen will both relieve pain and may help reduce inflammation. There are also first aid sprays containing benzocaine, a topical anesthetic that also acts on the nerve endings in the skin. Be careful, as this may sensitize the skin and lead to an allergic reaction upon subsequent applications of other medications in the “-caine” family. Don’t use other “-caine” anesthetics (such as lidocaine) for sunburn: They are readily absorbed into the bloodstream if the skin is broken and may cause immediate toxic or allergic reactions.
  • Try cooling lotions. Calamine lotion and aloe vera-based gels may provide some relief from pain and discomfort.
  • Don’t apply greasy creams or lotions such as petroleum jelly or baby oil. These types of oily products act to seal in the heat.
  • Powder your sheets. Sprinkle cornstarch powder on your sheets to minimize chafing.
  • If you are sunburned all over your body, try an oatmeal bath. The oatmeal soothes the skin and reduces inflammation. You can buy colloidal oatmeal bath products (such as Aveeno) in drugstores. Or make your own oatmeal soak at home by finely grinding a cup of dry instant oatmeal in a blender or food processor. Scatter the oatmeal in a tub of cool water and soak for a while. (Cornstarch works equally well.)

How to prevent sunburn

Sunburn is easily avoidable if you take some simple precautions. These include using an effective sunscreen with a sun protection factor (SPF) of 15 or higher (choose one that says “broad spectrum” on the label, meaning that it protects against UVA as well); wearing a broad-brimmed hat and tightly woven clothing to minimize exposed skin; and avoiding long sun exposure, even if you are wearing a sunscreen. Also make sure that children, especially infants, are well protected.

African-Americans and other people with comparatively dark skin probably need less sun protection than light-skinned people because their skin has a higher concentration of melanin—a pigment that absorbs UV rays. This is the skin’s defense against the sun. African-Americans seldom develop skin cancer and are less susceptible to sun-induced wrinkles. Among people who are not genetically dark-skinned, those who tan easily appear to be less susceptible to skin cancer—but they still need protection against UV rays.

When to call your doctor

Most sunburns are first-degree burns that affect the outer skin layer, cause no blistering, and can be treated readily with home remedies. However, contact your physician if:

  • You develop a fever or experience chills, nausea, or disorientation.
  • Fluid-filled blisters form. Secondary infection is a possibility.
  • The pain is especially severe. This could be a severe second-degree or a third-degree sunburn that has not only damaged the epidermis but the underlying nerves and subcutaneous tissue as well.

What your doctor will do

After an examination, your doctor may remove the fluid from any blisters. If infection has occurred, an antibiotic may be prescribed.