They range in size from small pin-head size to the size of a quarter. They can appear suddenly and often suddenly disappear. Sometimes they may last only 24 hours. Usually they hang around from a couple days to 3 weeks. Some experts believe these painful mouth irritations are contagious, but others disagree.
Canker sores occur most often in females for some reason.
They are also occasionally associated with vitamin deficiencies. Stress is, however, probably the most common cause of these sores. A health care provider will sometimes prescribe a mouthwash that contains antibiotics. Rinsing your mouth with warm salt-water often speeds up healing. Never use more than one teaspoon of salt per glass of warm water, and DO NOT swallow this mixture.