Corns and calluses are both a thickening of the outer layer of skin. This thickening is known medically as hyperkeratosis. Corns and calluses develop as part of the skin's normal defense against prolonged rubbing, pressure and other forms of local irritation.

Corns and calluses are often confused, but they're not the same thing. Corns are smaller than calluses - less than a quarter-inch in diameter - and have a hard center. Corns usually develop on the tops and sides of your toes and can be painful. Calluses, which may feel rough, are rarely painful and vary in size and shape. Calluses usually develop on your palms and soles, especially underneath the bottom ends of your foot bones (metatarsals).

Although corns and calluses can be unsightly, for most people, eliminating the source of friction or pressure helps corns and calluses disappear. If you have diabetes or another condition that causes poor circulation to your feet, you're at greater risk of complications.

Causes
You develop corns and calluses from the pressure and friction of repetitive actions. Causes include:

• Ill-fitting shoes.
• When shoes are too tight or have heels that are too high, they compress areas of your foot. When they're too loose, your foot may repeatedly slide and rub against the shoe. Your foot may also rub against a poorly placed seam or stitch inside the shoe.
• Skipping socks. Wearing shoes and sandals without socks can lead to friction on your feet. Socks that don't fit properly also can be a problem.

Prevention
Eliminating sources of friction or pressure should help you prevent corns and calluses from developing. These approaches may help:

Wear shoes that give your toes plenty of room. If you can't wiggle your toes, your shoes are too tight. Have your shoe shop stretch your shoes at any point that rubs or pinches.

Self-care
These suggestions may help you clear up corns and calluses:

• Wear comfortable shoes.
• Stick to loosefitting, cushioned shoes until your corn or callus disappears. Use over-the-counter pads.
• Apply pads to protect areas where corns and calluses develop. Be careful using over-the-counter liquid corn removers or medicated corn pads. These contain salicylic acid, which can irritate skin and cause infection, especially in people with diabetes and poor circulation. Thin your thickened skin.

During or after bathing, rub corns or calluses with a pumice stone or washcloth to help remove a layer of toughened skin. Never cut or shave corns or calluses, because you could introduce an infection.

If a corn or callus becomes very painful or inflamed, see your doctor. If you have diabetes or poor circulation, call your doctor before self-treating corns or calluses. Even a relatively minor injury to your foot could lead to an open sore (foot ulcer) that's difficult to heal.

The foot health information provided on this site is for general information purposes only, and cannot replace the expert advice of a qualified professional. We recommend seeking professional advice before embarking on any form of self treatment. Neither the content or any other service provided through this web site is intended to be relied on for medical diagnosis or treatment.