Calluses, or thickened skin, result from on-going friction or pressure on a particular area of skin. On the foot, calluses (hyperkeratosis) commonly occur on areas subjected to pressure and impact: the heels, balls of the foot, and the big toe. Calluses cause irritation and pain as the thickened skin continues to be exposed to pressure or rub against footwear.

Some calluses are painful and sore; the nerves are inflamed and fluid-filled sacs form underneath the callused area. Orthotic inserts and properly fitting footwear can prevent and alleviate calluses. Cortisone injections can provide rapid pain relief of inflammation and pain. For cases of heel callus formation resulting from a metatarsal bone deformity, surgery may be necessary to correct the bone and lessen the pressure.

To reduce calluses, soak affected feet in warm, soapy water, then rub the skin with a pumice or appropriate foot file; apply a thick moisturizing cream afterward to keep the skin soft. There are over-the-counter callus removers (always check with a doctor before using any medication; these particular treatments contain chemicals and can cause burns). Podiatrists also have methods for reducing calluses.

Similarly, corns form on the toes due to friction or pressure from rubbing against footwear or even other toes. The friction and pressure thickens the skin and inflames underlying tissue. Corns can be soft; these are open sores between the toes. Hard corns develop on top of the toes or on the outside of the little toe. Ill-fitting footwear and toe deformities can cause corns.

Treat corns by soaking the foot in warm, soapy water, then rubbing the skin with a pumice or appropriate foot file. Donut-shaped foam pads can reduce friction and pressure on the corn. Podiatrists also have methods for reducing corns.