An abscess occurs when an infection causes a pocket of pus to develop. Abscesses can develop on the skin, in the mouth, or inside the body. Bacterial infections typically cause abscesses. Pus develops ...

Medically reviewed by Jennifer Schwartz, MD Key Takeaways Pus forms when the immune system's white blood cells fight an infection.Pus can be different colors and may emit a foul odor if the infection ...