How effective is baking soda in treating canker sores, and what is the recommended usage?

Reviewed by Yoshinori Abe, MD

Internal Medicine

Baking soda may help relieve canker sore pain by neutralizing acids in the mouth that irritate the sore. To use it, dissolve 1 teaspoon of baking soda in a half-cup of warm water, then swish the rinse around your mouth for 15–30 seconds before spitting it out. This simple home remedy can reduce inflammation and promote faster healing.

However, canker sores can sometimes signal an underlying issue such as a vitamin deficiency, food sensitivity, or immune condition. If your sores are frequent, unusually large, or slow to heal, it's worth investigating further. Take a free, instant, online symptom check to better understand what may be causing your discomfort and get personalized guidance on your next steps.

Reviewed for medical accuracy: 07/14/2026

Important Next Steps

Discover likely causes of canker sores Learn if your sores need care today See if it could be something serious Find OTC treatments for canker sores Find a doctor for mouth sores Understand home remedies for canker sores Find out what’s causing sore mouth pain

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Explanation

Baking soda, also known as sodium bicarbonate, can be used to help ease the discomfort caused by canker sores. It works by neutralizing acids in the mouth, which can reduce irritation and pain.

How to Use Baking Soda for Canker Sores:

Make a Rinse: Mix one teaspoon of baking soda with half a cup of warm water.
Rinse Your Mouth: Swish the mixture around your mouth for about 30 seconds, then spit it out. Do not swallow the mixture.
Repeat: You can use this rinse several times a day as needed to help with the pain.

It's important to note that while baking soda can help with the pain, it does not cure canker sores. If your canker sores are very painful, last a long time, or keep coming back, you can use our free symptom checker to better understand your symptoms and determine if you should talk to a healthcare provider.

(References)

MacDonald J. (2002). Canker sore remedies: baking soda. CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne, 11949979.

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