4. Rinse with milk of magnesia
Another home remedy that can provide fast relief for a canker sore is the milk of magnesia. This white liquid is a suspension of hydrated magnesium carbonate that has been mixed together with water. It is commonly used as an antacid to treat heartburn, as it contains natural properties that act as an antacid. Milk of magnesia can be used to do more than easing the pain that is associated with heartburn; it can also be a highly effective home remedy for canker sores.
The same antacid qualities that neutralize the acids that cause heartburn can also neutralize the acids within the mouth that can cause a stinging or burning sensation in a canker sore. To use milk of magnesia, swish it around your mouth, concentrating on the site of the sore. Alternatively, you can dab a bit of it right onto the canker sore.