Asked by: Paul Layfield, via email
Blisters are one of the skin’s ways of protecting itself from harm, such as excessive friction (new shoes that rub), burns, irritating substances or allergies. Fluid collects between the outermost skin layer – the epidermis – and the layer below – the dermis – which are usually firmly connected. This bubble of fluid, most often a clear liquid called ‘serum’, shields the skin structures below from further damage, allowing healing. So as tempting as it is, it’s best not to pop a blister.
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