A felon is an infection in the fleshy part of the fingertip. It can cause a buildup of pus in the tip. This leads to painful pressure and damage to tissue.

Prompt medical attention is needed for a felon. It can stop the spread of the infection and prevent death of nearby tissue.

Infection Can Spread to the Bone

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Felon is caused by bacteria that has passed through a break in the skin. Common breaks on fingertip include a splinter, a paper cut, or needle puncture.

Once the bacteria is in the skin it can grow. The immune system sends blood cells to attack the bacteria. The dead bacteria and immune cells build up in the area. This build up is known as pus.

The swelling and pus can create a lot of pressure in the small area. The pressure can slow or stop blood flow to the area. This will cause extra damage to nearby tissue.

Risk Factors

Factors that may increase your chances of a felon include:

  • A weakened immune system
  • Medications that affect how the immune system works
  • Repetitive finger sticks, common with blood tests or blood glucose checks
  • Occupations or sports that carry a high risk of hand injury


A felon causes:

  • Rapid, throbbing pain
  • Swelling in the soft tissue of the fingertip
  • Redness and warmth (not always present)


You will be asked about your symptoms and health history. A physical exam will be done. The doctor can diagnose a felon based on appearance. Some tests may be done to see if there is tissue damage.

A sample of fluid from the area may be taken. It will show the exact type of bacteria that is causing the infection. It may be needed for severe infections or those that don’t respond to treatment.


Treatment will be started right away with antibiotics. They are often effective for most bacterial infections. Antibiotics may be given through an IV or by mouth. They type of antibiotic may be changed if the infection does not respond as expected.

Surgery may be needed if there is severe swelling or tissue damage. Surgical steps may include:

  • Opening skin over the area—will allow fluids and pus to drain out
  • Removal of damaged or dead tissue
  • Amputation —if there is severe tissue damage


Injuries are usually the result of an accident. These are hard to prevent.

Proper care of your cut may decrease the risk of infection:

  • Wash the cut out immediately. Apply antibiotic ointment and a bandage.
  • Watch for signs of infection. This include redness, swelling, and warmth.
  • If you notice a growing infection, get prompt medical care.

Family Doctor—American Academy of Family Physicians

Centers for Disease Control and Prevention


Health Canada

Public Health Agency of Canada


Cellulitis infection—finger felon. Sports Injury Clinic website. Available at: Accessed March 16, 2018.

Clark DC. Common acute hand injuries. Am Fam Physician. 2003;68(11):2167-2176.

Felon. Merck Manual Professional Version website. Available at: Updated November 2016. Accessed March 16, 2018.

Rigopoulos N, Dailiana ZH, et al. Closed-space hand infections: diagnostic and treatment considerations. Orthop Rev (Pavia). 2012;4(2):e19.

Last reviewed March 2018 by EBSCO Medical Review Board James P. Cornell, MD  Last Updated: 7/23/2018