A callus is an abnormal thickening of the top layer of skin, which is composed of the natural protein, keratin. Calluses can form on areas that are repeatedly exposed to friction or pressure. They are usually painless or only mildly painful.
A corn is a small, thickened area of skin that forms on the toes. Corns put pressure on the underlying skin against the bone. They are usually painful.
Calluses and corns form as protective pads of skin in response to repeated friction or pressure. Causes include:
Factors that may increase the risk of calluses and corns include:
Symptoms of calluses include:
Symptoms of corns include:
The doctor will examine the skin where a corn or callus has formed. Diagnosis is based on symptoms and visual observation of the corn or callus. They are easily distinguished by:
The doctor may need to use a scalpel to reveal the layers of the skin growth to make sure that it is a corn or callus, rather than a wart.
Treatment of calluses and corns usually includes self-care and medication. In severe cases, minor surgery may be necessary. People with diabetes or circulatory problems should always see a medical doctor or podiatrist for treatment. Self-treatment may lead to severe infection in these individuals.
Applying keratin-dissolving medication (such as salicylic acid) can help dissolve calluses and corns more quickly. Apply medicine carefully because it contains acid that may damage nearby healthy skin.
In severe cases, calluses and corns may need to be shaved off with a scalpel by a doctor. More extensive surgery may be needed to correct foot deformities that cause extremely painful or debilitating corns.
If you are diagnosed as having a callus or corn, follow your doctor's instructions.
American Academy of Family Physicians
American Orthopaedic Foot and Ankle Society
Canadian Orthopaedic Association
Canadian Orthopaedic Foundation
Callus. EBSCO DynaMed website. Available at: https://dynamed.ebscohost.com. Updated August 27, 2012. Accessed September 14, 2012.
Corn. EBSCO DynaMed website. Available at: https://dynamed.ebscohost.com. Updated August 27, 2012. Accessed September 14, 2012.
Corns. American Academy of Orthopaedic Surgeons website. Available at: http://orthoinfo.aaos.org/topic.cfm?topic=A00153. Updated March 2001. Accessed July 24, 2012.
Corns and calluses. Mayo Clinic website. Available at: http://www.mayoclinic.com/health/corns-and-calluses/DS00033. Updated May 24, 2012. Accessed July 24, 2012.
Last reviewed October 2012 by Brian Randall, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.