Sunburn is the physical response of the skin to damage by overexposure to UV radiation; the duration and intensity of UV radiation corresponds to the severity of the sunburn. UV radiation, specifically the UVB wavelengths, penetrates the skin and burns the tissue, often damaging skin cells beyond repair. For more details on this process, refer to the Sunburn article.
Sunburn is extremely common, with surveys showing that 42% of people get sunburnt at least once annually. Solar UV radiation is the most common cause of sunburn, yet any form of UV radiation, including that emitted by sunbeds and solariums, can produce a sunburn reaction.
Red coloured skin, characteristic of sunburn, manifests between 2 and 6 hours following UV exposure. The burn further develops for the following 1-3 days. Symptoms may include:
- Redness and inflammation (erythema);
- Pain or stinging;
- A hot or burning sensation;
- Nausea and vomiting;
- Faintness or weakness;
- Tender, aching or throbbing skin;
Figure 1: Skin damaged by sunburn
Sunburn relief – first aid
The following recommendations are provided courtesy of the Lucile Packard Children’s Hospital at Stanford. Please be advised that this information is not a substitute for medical advice by a professionally qualified health care provider.
In the event of sunburn, the following steps can be taken to provide sunburn relief and reduce its symptoms:
- Apply a cool compress to the area throughout the day to decrease heat and pain from the sunburn.
- In the case of large area burns, take several cool baths for 10 minutes at a time. Ensure water is not so cold as to induce a chill. Adding baking soda to bathwater may improve symptoms; approximately 4 tablespoons (55g) for a full bathtub. Avoid using soap on the affected area as this may irritate sunburnt skin.
- Administer either acetaminophen (paracetamol) or ibuprofen (anti-inflammatory) medication to ease pain, swelling and fever. Refer to individual medications for directions and safety information.
Figure 2: Sunburnt skin
- When it becomes tolerable to touch the skin, apply an aloe gel, topical pain reliever or moisturiser. While the damaged skin may still flake off, a moisturiser will stop the underlying skin replacing it from becoming dry and rough. Products containing the ingredients Benadryl and benzocaine are not recommended due to their propensity to irritate skin and provoke allergic reaction. Alternatively a steroid ointment (1% hydrocortisone) can be used three times per day, for two days; this minimises pain and inflammation.
- Do not burst blisters as this can lead to infection. Open blisters can be treated by removing dead skin with alcohol sterilized scissors. An antibiotic cream should then be applied twice daily for three days to prevent infection. Remove the previous application with warm water prior to subsequent treatments.
- Avoid further sun exposure to the affected area until the sunburn has completely healed.
- Drink plenty of water. This replaces fluid lost through the sunburn and helps prevent dehydration, another possible effect of excessive sun exposure.
- In the case of acute sunburn (where there is severe burn or blistering, fever, chills, nausea, faintness or extreme pain), it may be necessary to consult a doctor for additional treatment. Severe sunburn can have dangerous consequences and is potentially fatal; in such cases seek emergency medical attention.
Sunburn is classified according to level of severity:
Level of Sunburn
Mildest form of sunburn, characterized by reddened, inflamed skin (erythema).
More intense erythema and slight blistering.
Deep reddening, extensive blistering, strong pain and possibly lightheadedness, headache, vomiting, nausea, chills or fever. Seek medical treatment.
Occasionally, severe sunburn is accompanied by heat stroke, or sunstroke, where the body’s internal temperature rises above 40.5 ËšC. Symptoms of heat stroke may include: very high body temperature, dry swollen tongue, rapid pulse, shallow breathing, faintness, headache, fever, chills, confusion, nausea or loss of consciousness. Heat stroke is a medical emergency and can lead to death if not treated promptly.
Long term effects of sunburn
Sunburns are a sign of UV damage to skin cells. The discomfort of a sunburn episode itself may be brief and the burn heals, however the damage incurred by the skin is permanent. The UV damage to cells compounds and can produce lasting effects, most significantly, photoaging and the development of skin cancer.
The cumulative amount of UV exposure during one’s lifetime is a central factor which contributes to the development of skin cancer. There is much evidence to suggest that a history of numerous, severe sunburn incidents, particularly during childhood, is a high risk factor for the development of melanoma, the most lethal type of skin cancer, later in life.
UV radiation also promotes photoaging, premature aging of the skin, caused by damage to the collagen fibres which give skin its suppleness and flexibility. Photoaging presents as wrinkles, age spots, broken blood vessels and leathery, sagging or discoloured skin; such damage is irreversible.
The only way to prevent sunburn is to protect skin from UV radiation. Good methods of sun protection include:
- Avoiding sun exposure during periods of high UV (generally 10 am till 3 pm) and seeking the shade where possible.
- Wearing protective clothing; including broad-rimmed hats and closed-toed shoes.
- Regularly and liberally applying a sunscreen with an SPF of 15 or higher.
Figure 3: Sunburn prevention
False. The amount of UV radiation required to elicit a burn response varies greatly from person to person, individuals with fairer skin (type I & II) are more susceptible and their skin may burn in as little as 10-15 minutes.
False. Darker-skinned individuals are less sensitive to the sun due to higher levels of the photoprotective pigment melanin. They may rarely burn, or burn more slowly than lighter-skinned people. However, it is possible for any person to get sunburnt given sufficient UV exposure, regardless of their skin type.
False. Butters and oils seal in the heat of sunburn furthering damage to skin and preventing it from healing. Other folklore remedies containing fats which worsen a sunburn include; petroleum jelly, baby oil and lavender oil.
False. Methylated spirits may provide symptomatic relief as the alcohol cools the sunburnt area as it evaporates, however, it is also known to be drying and irritating to skin. Chemists stock a variety of gels and lotions to ease the heat and pain associated with sunburn; aloe vera is another alternative commonly used to soothe burnt skin.
False. UVB radiation, the wavelength largely responsible for sunburn, cannot penetrate the glass commonly used in windows, however UVA can. So although glass significantly decreases your chances of becoming sunburnt it does not protect your skin from the damaging effects of UVA radiation.
False. Similarly to glass, clouds block out some, but not all, wavelengths of UV radiation. Therefore, it is possible to incur skin damage despite full cloud coverage.
- Cancer Research UK, 2009, Can glass block sun rays that cause skin cancer?, accessed 30th June 2010, <http://www.cancerhelp.org.uk/about-cancer/cancer-questions/can-glass-block-sun-rays-that-cause-skin-cancer>.
- Lucile Packard Children’s Hospital, 2010, Facts About Sunburn, accessed 28th June 2010, <http://www.lpch.org/DiseaseHealthInfo/HealthLibrary/burns/sunburn.html>.
- Lucile Packard Children’s Hospital, 2007, Sunburn, accessed 30th June 2010, <http://www.stanfordchildrens.org/en/topic/default?id=second-degree-burns-partial-thickness-burns-90-P01757>.
- NSW Government, 2013, Heat-Related Illness including Heat Stroke, accessed 22nd December 2015, <http://www.health.nsw.gov.au/environment/factsheets/Pages/heat-related-illness.aspx>.
- Skin Cancer Foundation, n.d, Sunburn: Facts about Sunburn and Skin Cancer, accessed 28th June 2010, <http://www.skincancer.org/facts-about-sunburn-and-skin-cancer.html>.
- SunSmart Victoria, 2009, Sunburn, accessed 28th June 2010, <http://www.sunsmart.com.au/browse.asp?ContainerID=1561>. Link no longer active.