July 6, 2011 -- Sunburn is one of the summer's most enduring stings, leaving a sore, red, peeling patch long after the day's rays give way to cooler nights. Ointments and Aspirin can help soothe the sear. But the pain, part of the body's plea for shade and sunscreen, is inevitable.
That could change.
British researchers have discovered a molecule responsible for the persistent pain caused by sunburn, offering hope for a treatment that could one day block it.
"It wasn't known before that this protein was implicated in any kind of pain," said Stephen McMahon, professor of physiology at Guy's Medical School in London. "If you wanted a cure for sunburn pain, we may have found that."
The protein, called CXCL5, was elevated in painful sunburns. And blocking the protein's effects in a rat model of sunburn relieved the pain. The study was published today in Science Translational Medicine.
But McMahon, a long time pain researcher, thinks blocking sunburn pain is a bad idea.
"Pain plays a protective role," he said, explaining how the sensation alerts its victim to looming danger. "Stopping pain is not necessarily a good thing."
Sunburns are the body's response to ultraviolet radiation, which kills some skin cells and permanently damages the DNA of others, sometimes leading to skin cancer later on. In an attempt to save the damaged cells with oxygen and nutrients, the body pumps more blood to the skin, turning it red. And the swollen blood vessels ooze plasma, causing blisters.
"By the time you see your skin turning pink, it's almost too late," said Dr. Darrell Rigel, dermatologist at NYU Langone Medical Center in New York City. "The damage has already happened."
That damage, Rigel said, is impossible to undo.
"The best thing you can do is protect yourself from the sun," he said. "Wear a broad-brimmed hat, avoid being outside when the sun is at its strongest, and use sunscreen. We know those three things together lower sunburn risk and subsequently lower the risk of skin cancer."
But the sun is sneaky. And even those who protect themselves fall victim to the odd pink shoulders or red feet. Rigel shared these tips for beating the pain and protecting the tender skin after a getting burned:
Take an Aspirin
Aspirin is a non-steroidal anti-inflammatory that acts directly on chemicals known to play a role in sunburn pain. It will work better than acetaminophen.
Keep It Cool
The burn will release heat because of the increased blood flow. Sunburn creams that contain menthol will cool the skin.
Stay Hydrated, Moisturized
Damaged skin loses its ability to retain water. Drink lots of water, and use a heavy moisturizer like Vaseline. Avoid using topical anesthetics or antihistamines, which can lead to reactions on the newly exposed, immature skin.
Resist the Urge to Peel
Normally it takes about 28 days for the cells at the base of the skin to work their way to the surface, where they die and are shed as individual cells. But when that process is packed into fewer days by a burn, the cells have less time to separate from their neighbors, and tend to come off in sheets. Let this happen naturally. Peeling the skin can leave a scar, and can even lead to an infection.
Stay Under Cover
If you have a blistering sunburn, you should stay out of sun for a week. The skin is already damaged and more sun will make it worse. If you have to go out, wear a hat and protective clothing. The best protection comes from fabric that is wooly, dark and a tight weave -- not ideal for 90 degree heat. But new synthetic fabrics are light weight, quick to dry and offer up to 50 SPF.
The tops of the feet, shoulders, nose and ears are the body parts most often missed during sunscreen slathering.