What is the difference between Canker sores and Cold sores?
Cold sores or fever blisters are caused by the herpes simplex virus and are usually relatively easy to identify.
There is another condition which causes ulcers inside the mouth known as Canker sores which are not a form of herpes, however, they are often confused and mistaken for cold sores.
Canker sores are ulcerations, especially of the lip or oral mucosa and can be caused by acute stress, trauma to the area in your mouth, allergies, or by a reaction to a particular bacteria.
Canker sores are not considered to be contagious. Cold sores and mouth herpes on the other hand are caused by the herpes simplex virus and can be very contagious.