My canker sores usually flare up when there is a lower resistance in my body. If I get, especially a flu, or some other typr of virus. I have found that rinsing with very diluted salt water help them to heal more quickly. Make sure that the salt content in the water is not too high, because this will make them worse. Also, there is a mouthrinse called peroxly that is mint flavored peroxide. This heals them quickly. There is a prescription cream that really does the trick if you have an prescription card. it is called Zovirex. It is prescribed for herpes sores. This will heal a fever blister or cancer sore in 24 to 48 hours if your doctor feels that it is indicated in your case, and will not interact with the medications you are currently taking.