- Canker sores are not actually contagious
- Cold sores or fever blisters are caused by the herpes virus
- Cold sores or fever blisters can be found on the lips or inside the mouth
Canker sores are not like fever blisters or cold sores. This means that they are not actually contagious. Canker sores are actually quite common and there is a huge chance that you will have to deal with this problem at some point in your life. The main difference with cold sores and fever blisters is that they are caused by the herpes virus (HSV1). These sores can occur on the lips or around it, and they can also be seen inside the mouth, specifically on the different soft tissues. Canker sores on the other hand, are small ulcers that have red borders as well as a white or yellowish base. They are also known to be very painful. Although they can also be found inside the mouth, they typically occur on moveable tissues such as the inner portion of the lips, the cheeks, and underneath the tongue.