Cold sores and cankers are not the same, but they are both types of sores. Canker sores occur inside the mouth, while cold sores are generally found on or near the lips.

A canker sore is a small ulcer with a white or grey base and red border. There can be one or a number of sores in the mouth. Canker sores are very common and recur often. Canker sores are very difficult to treat. There is no proven technique that will eliminate ulcers or speed the recovery time once they appear. There are a few medications that will give temporary relief from the pain, but they need to be started as soon as symptoms appear. Canker sores usually heal in about a week or two. Anti-microbial mouth rinses may help reduce the irritation. Over-the-counter topical anaesthetics can also provide relief.

A cold sore, which is also called fever blister and is caused by the herpes simplex virus, is composed of groups of painful, fluid-filled blisters that often erupt around the lips and sometimes under the nose or the chin. This virus is very contagious and you should take care not to come into contact with a herpes lesion. Over-the-counter topical anaesthetics can provide temporary relief and prescription antiviral drugs may reduce these kinds of viral infections.