Have you ever put on a pair of second-hand shoes and then noticed a small yellow bump forming on your toe? It can feel uncomfortable and even worrying at first, but in most cases it’s harmless. That yellow bump is usually a corn or callus—a patch of thickened skin that develops when your body tries to protect itself from repeated rubbing or pressure.

How to Treat It

• Soak and smooth: Soak your feet in warm, soapy water for 10–20 minutes, then gently use a pumice stone or emery board. Do not cut the skin yourself.

• Reduce friction: Apply corn pads, moleskin, or gel toe protectors.

• Moisturize: Use creams containing urea to soften thickened skin.

• OTC treatments: Salicylic acid pads can gradually break down corns.

If the area becomes painful, red, swollen, produces pus, or does not improve after a couple of weeks, it is best to see a podiatrist. They can safely treat the problem and check for underlying causes such as bunions or bone spurs.

Preventing Problems with Used Shoes

• Clean and disinfect second-hand shoes thoroughly, ideally with antifungal sprays.

• Wear socks to reduce friction and moisture.

• Break shoes in slowly.

• Choose breathable materials and the correct size.

That yellow bump is your skin’s way of signaling too much friction. Fixing the shoe fit usually solves the problem quickly—and when foot issues persist, professional care can help you get back to comfortable, healthy steps.