A tonsil stone, also known as a tonsillolith, is a lump of hardened material stuck in a tonsil. Some tonsils develop small pits in which food or mucus get caught. Bacteria grows on the bits that collect in the pit.

Symptoms can include the feeling of something stuck in the throat, bad breath and a bad taste in the mouth. Other symptoms might include a long-lasting or repeated sore throat. Some people have no symptoms.

Many tonsilloliths need no treatment. A health care provider can remove larger ones during surgery.