3 doctors weighed in:

What symptoms make you think of canker sore?

3 doctors weighed in
Dr. Steven Machtinger
Internal Medicine - Allergy & Immunology
2 doctors agree

In brief: Isolated mouth sore

Cankers are isolated shallow ulcers on the inside of the lip, lining of the cheeks or on the tongue.
They hurt even though they're no more than 2-3 millimeters in diameter. No fever. You can't help run your tongue over it - that probably inhibits healing. Multiple ulcers on the lip think herpes type 1. Multiple sores in back of mouth with fever think herpangina or hand-foot-mouth syndrome.

In brief: Isolated mouth sore

Cankers are isolated shallow ulcers on the inside of the lip, lining of the cheeks or on the tongue.
They hurt even though they're no more than 2-3 millimeters in diameter. No fever. You can't help run your tongue over it - that probably inhibits healing. Multiple ulcers on the lip think herpes type 1. Multiple sores in back of mouth with fever think herpangina or hand-foot-mouth syndrome.
Dr. Steven Machtinger
Dr. Steven Machtinger
Thank
Get help from a real doctor now
Dr. Cindy Juster
Board Certified, Pediatrics
33 years in practice
2M people helped
Continue
108,000 doctors available
Read more answers from doctors