Signs & Symptoms of Canker Sores

What Are the Symptoms of a Canker Sore?

Ouch! You have a painful sore inside your mouth. Check to see if it's a canker sore by looking for these symptoms.
  • Canker sores begin as a small bump or red spot inside the mouth.
  • Sometimes a tingling or burning sensation signals a developing canker sore.
  • They progress rapidly to clearly defined spots in the mouth. They are small, but painful, ulcerations.
  • While canker sores are typically small, rarely one can be very large (2 or more inches) and can take as long as 6 weeks to fully heal.
  • Most canker sores heal without medication, usually within 7-14 days.
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