You’ve laced up your brand new running shoes; they’re featherlight and oh-so-snug. Goodbye, couch. Hello, 5K. But 10 minutes into your run, and you feel a painful rub. Your ankles start to burn with every footfall.
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The next morning, the ankles look worse. The angry, red skin has formed sacs of fluid (a.k.a. blisters).
Depending on the cause, blisters can be filled with any of the following:
“The fluid works to further prevent damage to the skin below and to allow the skin to heal,” says Shilpi Khetarpal, MD.
Should you pop or break a blister?
The short answer? No.
“Blisters should never be unroofed as this is your body’s way of forming a bandage,” Dr. Khetarpal says.
Most people should leave blisters alone and let them heal on their own. But for certain people at risk for infection, a doctor may choose to use a sterile needle to allow fluid to drain.
This is especially the case for people with compromised immune systems (people with HIV, diabetes, or those who take medications that suppress the immune system).
Are you prone to getting blisters?
Some preexisting skin disease can put you at risk for blisters.
Or the cause could be as simple as walking around with wet or damp feet (whether from sweat or from being in water).
“In either case, you’re more prone to blisters because the skin barrier is compromised,” Dr. Khetarpal says.
Besides the feet, blisters also commonly form on people’s hands — as both of these areas undergo repetitive friction and abrasion.
How do you prevent blisters?
Of course, the best way to prevent blisters is to wear shoes that fit you properly.
However, even with proper fit, new shoes are still more likely to cause blisters than your worn-in favorites. Some materials, like leather, need some wear to soften and mold to your feet.
You can use bandages in key areas to protect skin as you break in new shoes. Also, foot powders can help by keeping feet cool and dry.
If you tend to sweat a lot, it’s a good idea to either change your socks often or to wear sandals when it’s possible.
Can blisters scar?
The depth of the blister determines whether or not it will scar.
“The deeper the injury (particularly when it comes to a chemical or heat burn), the more likely it is for a scar to form.
Typically, friction blisters do not scar as they tend to be more superficial,” Dr. Khetarpal says.
When should you see a doctor?
While blisters often form because of direct irritation of the skin, some medical conditions also can cause blisters all over the body.
If this happens, it is important you see a dermatologist for evaluation and treatment.