An ingrown nail grows into the flesh instead of over it and usually affects the toes, particularly the big toe. The site of an ingrown nail can be painful, tender, red, swollen, and can sometimes develop pus.
Ingrown nails are most often caused by:
Most ingrown nail problems can be prevented by proper nail care, such as cutting nails straight across, and by wearing shoes and socks that fit well. Home treatment, such as soaking the affected nail in hot water, can often help relieve pain. Antibiotics may be needed for an ingrown nail that becomes infected. A severely ingrown nail may have to be partially or completely removed.
WebMD Medical Reference from Healthwise