How long do lesions take to heal when you bite your tongue?

Most mouth sores, such as a lesion from biting the tongue, heal on their own within 10 to 14 days, although some can last for as long as six weeks, notes MedlinePlus. Patients should contact their physicians for advice if a mouth lesion lasts for more than two weeks.

Cuts on the tongue or cheeks from biting are the most common mouth injury in children, according to Seattle Children's Hospital. They rarely need stitches and typically heal quickly. Some home treatments to help ease the pain include taking pain relievers, gargling with salt water, and avoiding hot, spicy or citrus food, according to MedlinePlus.