Foot Blisters: How to Prevent, Treat and Heal Them

Reviewed by the FootWell editorial team · Edited by Mustafa Bilgic · Updated June 2026 · ~6 min read

Blisters form when repeated friction and heat cause the upper layers of skin to separate and fill with fluid. They are common during breaking in new shoes or long walks, and most can be prevented with the right socks, fit and friction control.

Why blisters form

Three factors combine to create a blister: friction, moisture and heat. When skin rubs repeatedly against a sock or shoe, the layers shear apart and fluid cushions the damaged area. Damp feet blister far more easily than dry ones.

Preventing blisters

• Wear moisture-wicking socks — avoid cotton, which holds sweat
• Make sure shoes fit properly and are broken in gradually
• Address 'hot spots' immediately with tape or a blister plaster
• Use friction-reducing balm or powder on prone areas
• Keep feet dry; carry a spare pair of socks on long walks

Treating a blister

1. Leave small, intact blisters alone — the skin is a natural barrier.
2. Protect them with a cushioned blister plaster.
3. If a large blister must be drained, use a sterilised needle, leave the roof of skin in place, and cover it.
4. Watch for signs of infection: increasing redness, warmth, pus or red streaks.
5. Keep the area clean and dry while it heals.

Footwear that helps

Shoes with a smooth interior, the correct length (a thumb's width of room at the toes) and a secure heel prevent the sliding that causes blisters. Replace worn insoles that have lost their smooth surface.

Frequently asked questions

Should I pop a blister?

Leave intact blisters alone when possible. Only drain large, painful ones with sterile technique and keep the skin roof in place.

What socks prevent blisters?

Moisture-wicking synthetic or merino socks beat cotton, which traps sweat and increases friction.

Sources & further reading

• Blisters, NHS
• Blister care, Mayo Clinic
• Foot blisters, American Podiatric Medical Association (APMA)