Rinse with warm salt water several times a day
Rinse with baking soda and water
Use an over-the-counter canker sore gel or paste
Apply a topical oral anesthetic for pain relief
Avoid spicy, acidic, salty, and crunchy foods
Avoid alcohol-based mouthwash
Use a soft-bristled toothbrush
Keep the sore clean and dry
Take over-the-counter pain relievers if needed
Use ice chips to numb the area
Try a protective oral patch or barrier paste
Check for triggers like stress, mouth injury, or certain foods
See a dentist or doctor if it lasts more than 2 weeks, is very large, or keeps returning