Canker sores usually go away on their own within 2 to 3 weeks.
If your canker sore doesn't go away within 3 weeks or it's accompanied by a fever or difficulty swallowing a doctors visit is needed.
You can gargle with apple cider vinegar or apply the apple cider vinegar directly to the canker sore to get rid of the canker sore.
Apple cider vinegar contains antibacterial properties which can help kill off the bacteria and viruses that is causing the canker sore.
Applying a numbing agent or orajel to the canker sore can also get rid of the canker sore and make it feel better at the same time.