Sunburn — red, painful skin that feels hot to the touch — usually appears within a few hours after sun exposure and may take several days or longer to fade.
Intense sun exposure that results in sunburn increases your risk of certain complications and related skin diseases. These include dry, wrinkled skin, liver spots, actinic keratoses, and skin cancer, including melanoma.
You can prevent sunburn and the related skin conditions by protecting your skin whenever you're outdoors, even on cloudy days. If you do get sunburn, several home remedies and treatments can relieve your pain and speed the healing of your skin.
Pathophysiology.
Exposure to solar radiation has the beneficial effects of stimulating the cutaneous synthesis of vitamin D and providing radiant warmth. Unfortunately, when the skin is subjected to excessive radiation in the ultraviolet range, deleterious effects may occur. The most conspicuous is acute sunburn or solar erythema.[2]
Initially, UVR causes vasodilation of cutaneous blood vessels, resulting in the characteristic erythema. Within an hour of UVR exposure, mast cells release preformed mediators including histamine, serotonin, and tumor necrosis factor, leading to prostaglandin and leukotriene synthesis.[2, 3] Cytokine release additionally contributes to the inflammatory reaction, leading to an infiltrate of neutrophils and T lymphocytes.[4] Within 2 hours after UV exposure, damage to epidermal skin cells is seen. Both epidermal keratinocytes ("sunburn cells") and Langerhans cells undergo apoptotic changes as a consequence of UVR-induced DNA damage.[5, 6] Erythema usually occurs 3-4 hours after exposure, with peak levels at 24 hours.[7] Less intense or shorter-duration exposure to UVR results in an increase in skin pigmentation, known as tanning, which provides some protection against further UVR-induced damage.[8] The increased skin pigmentation occurs in 2 phases: (1) immediate pigment darkening and (2) delayed tanning. Immediate pigment darkening occurs during exposure to UVR and results from alteration of existing melanin (oxidation, redistribution). It may fade rapidly or persist for several days. Delayed tanning results from increased synthesis of epidermal melanin and requires a longer period of time to become visible (24-72 h). With repeated exposure to UVR, the skin thickens, primarily due to epidermal hyperplasia with thickening of the stratum corneum. UVR exposure also suppresses cutaneous cell-mediated immunity, contributing to nonmelanoma skin cancer and infectious disease development.[2]
Causes
Sunburns are caused by exposure to too much ultraviolet (UV) light. UV radiation is a wavelength of sunlight in a range too short for the human eye to see. UV light is divided into three wavelength bands — ultraviolet A (UVA), ultraviolet B (UVB) and ultraviolet C (UVC). Only UVA and UVB rays reach the earth. Commercial tanning lamps and tanning beds also produce UV light and can cause sunburn.When you're exposed to UV light, your skin accelerates its production of melanin. Melanin is the dark pigment in the epidermis that gives your skin its normal color. The extra melanin — produced to protect the skin's deeper layers — creates the darker color of a "tan." A suntan is actually your body's way of blocking the UV rays to prevent sunburn and other skin damage. But the protection only goes so far. The amount of melanin a person produces is determined genetically, and many people simply can't produce enough melanin to protect the skin well. Eventually, UV light causes the skin to burn, bringing pain, redness and swelling.
You can get sunburn on hazy or cloudy days. As much as 90 percent of UV rays pass through clouds. UV rays can also reflect off snow, ice, sand, water and other reflective surfaces, burning your skin as severely as direct sunlight
WAYS TO SOOTHE THE STING OF SUN BURNS
Extremely severe sunburn is agony. If it’s not serious enough for A&E but bad enough to stop you sleeping, here are some ways to soothe the stinging
Keep covered
The last thing you need when you’re burnt is to burn more, so keep out of the sun where possible and when you are out cover up in long-sleeves and trousers. Try linen, which is light enough to stop you overheating but gives you protection from the sun’s rays.
Cool it down
As with any burn, sunburnt skin feels hot to the touch and cooling it down is important to relieve the pain. You can buy over-the-counter cooling compresses, or make your own with a mixture of cold water and milk. Soak a clean, very soft cloth and press it onto the area every 15 minutes. You can also bath or shower in lukewarm water or try pouring this over the area.
Rehydrate.
As well as putting water on the burn topically, make sure you’re keeping your skin hydrated by drinking plenty of fluids. Don’t drink alcohol as this will dehydrate you and dry out your skin even more.
Once you’ve cooled the area, there are plenty of after-sun balms and lotions that can help soothe the pain and moisturise the skin. Pure aloe vera or gels containing it work well, as does calamine lotion, which can help with itching.
Treatments
If it’s really painful, try oral painkillers such as paracetamol or ibuprofen. You can also try a one per cent hydrocortisone cream, which is sometimes used for eczema and dry skin. Rubbing this directly onto the sunburn can calm irritation and inflammation. This should not be used on children under the age of two, on the face or genitals or if you broken the skin. A natural alternative would be honey, specifically manuka honey, which is anti-inflammatory and antibacterial and is thought to help the skin regrow cells.
When to go to A&E
Very serious burns may need emergency medical treatment. If it’s a baby or child, it’s best to get them checked out as their skin is far more delicate than ours. On adults, if the skin has blistered or you feel dizzy, nauseous or have a fever, head straight to A&E.
