A felon is an infection in the fleshy part of the fingertip. If left untreated, a felon can cause a buildup of pus, painful pressure, and damage to nearby tissue.

Prompt medical attention is needed to prevent complications such as spreading infection or death of nearby tissue.

Infection Can Spread to the Bone

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A felon can occur when bacteria enters the body through breaks in the skin like a splinter, a paper cut, or a puncture from a needle. Once the bacteria is in the skin it can grow and cause a reaction from the immune system. The dead bacteria and immune cells build up leading to a collection of pus.

The swelling from the infection and growth of pus can create a lot of pressure in the fingertip. High amounts of pressure can interfere with blood flow to the fingertip and damage 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 fingersticks, which can occur with blood tests or blood glucose checks
  • Occupations or sports that carry a high risk of hand injury


A felon causes rapid, throbbing pain and swelling in the soft tissue of the fingertip. The area may also be red and warm.


You will be asked about your symptoms and medical history. A physical exam will be done. A felon can be diagnosed by an exam of the finger. Further testing may be done to see if there is tissue damage.

A sample of fluid from the area may be taken to find the specific type of bacteria causing the infection. This may help guide treatment for severe infections or infections that don’t respond to standard treatment.


Treatment will focus on eliminating the infection and decreasing the risk of tissue damage.

Treatment will be started right away with broad-spectrum antibiotics. These medications are generally effective for most bacterial infections. Antibiotics may be given through an IV or by mouth. If needed, medications and dosing can be changed based on the specific bacteria.

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

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


It may not be possible to protect yourself from an injury to your finger. If you get a cut, wash it out immediately and apply antibiotic ointment and a bandage. Monitor for signs of infection such as redness, swelling, and warmth. If you notice a growing infection, get prompt medical treatment.