Cold sores and canker sores may appear similar but are quite different in terms of causes, symptoms,...



| Characteristic | Cold Sores | Canker Sores |
| Location | Outside mouth, on lips | Inside mouth, soft tissues |
| Cause | Herpes simplex virus | Multiple factors (stress, nutrition) |
| Transmission | Highly contagious | Not transmissible |
| Appearance | Fluid-filled blisters | White/yellow ulcers with red border |
