Furuncle, unspecified

This code represents a localized, acute bacterial infection of a hair follicle and surrounding tissue, resulting in a painful, pus-filled nodule. It is commonly known as a boil and can occur anywhere on the body where hair is present.

Assign this code when documentation indicates a furuncle without specifying the anatomical site. This code is appropriate when the provider's diagnosis is simply "furuncle" or "boil" without further detail.

• Avoid using this code if the anatomical site of the furuncle is documented; instead, use a more specific code from the L02.xx series.
• Do not confuse with carbuncles (L02.91), which are deeper and involve multiple hair follicles.
• If an associated cellulitis or abscess is documented, consider additional codes to fully capture the patient's condition.