Paronychia is a skin infection (fungal or bacterial) around a nail. Symptoms of redness or swelling can come on suddenly and last for a short period of time (acute), or symptoms can be ongoing or occur repeatedly (chronic).
The infection is more likely to develop from having the hands or feet in water repeatedly, or from an injury, such as biting or cutting off a hangnail or pushing back a cuticle.
Minor redness or swelling may clear up with home treatment, such as keeping the area clean. Some cases require treatment with topical antibiotics or antifungal medicine. Occasionally a doctor will need to drain the infected area.