A dark, painful spot suddenly appearing on your child’s foot can be alarming, but in many cases it is simply a blood blister caused by minor pressure or injury. Blood blisters develop when tiny blood vessels beneath the skin break while the outer layer of skin remains intact, trapping blood underneath and creating a dark red or purple bump.
Common causes include tight shoes, friction from running or walking, or a minor impact. Although they can look serious and feel tender, most blood blisters heal on their own within one to two weeks without requiring special treatment.
To help your child recover, avoid popping the blister, as the skin acts as a natural barrier against infection. Applying a cold compress can reduce pain and swelling, while keeping the area clean, dry, and protected from rubbing can prevent further irritation. If the blister is painful, limiting pressure on the foot may also help.
Parents should watch for signs of infection, including increasing redness, swelling, warmth, pus, or fever. Medical advice is also recommended if the blister develops without an obvious cause, becomes unusually painful, continues to grow, or keeps returning, as these symptoms may indicate another underlying condition.
In most situations, however, blood blisters are harmless and improve with simple home care. With a little patience and gentle treatment, the blister should gradually disappear, allowing your child to return to normal activities once the area has fully healed.