Most canker sores heal on their own within two weeks, but a few simple home treatments can cut down on pain and may speed up the process. The key is reducing irritation, keeping the area clean, and creating conditions that let the tissue repair itself faster.
Salt Water and Baking Soda Rinses
The simplest and most widely recommended home treatment is rinsing with salt water or baking soda. For a baking soda rinse, dissolve 1 teaspoon of baking soda in half a cup of warm water. For salt water, use roughly the same ratio. Swish the solution around your mouth for 30 seconds, then spit it out. You can do this several times a day, especially after meals.
Both rinses work by shifting the chemical environment inside your mouth. Your saliva and the foods you eat create an acidic environment that irritates the open sore and slows healing. Baking soda neutralizes that acid, while salt water draws fluid out of inflamed tissue, which reduces swelling. Neither will sting as much as you might expect, though salt water on a fresh sore can be briefly uncomfortable.
Honey Applied Directly to the Sore
Applying a small amount of honey directly to the sore is one of the better-studied home remedies. In a clinical trial of 94 people with minor canker sores, honey outperformed both a prescription steroid cream and a standard protective paste. The honey group had faster reduction in ulcer size, fewer days of pain, and less redness around the sore. Honey has natural antibacterial properties and forms a protective coating over the ulcer, shielding it from further irritation.
Use raw, unprocessed honey if you have it. Dab a small amount onto the sore with a clean finger or cotton swab three to four times a day. It will dissolve fairly quickly in your mouth, so reapplying throughout the day helps maintain coverage.
Protecting the Sore From Irritation
Much of what makes canker sores miserable isn’t the sore itself but the constant re-irritation from food, drinks, and your own teeth. A few practical steps make a real difference:
- Avoid acidic and spicy foods. Citrus fruits, tomatoes, vinegar-based dressings, and anything with chili or hot sauce will aggravate the sore and extend your discomfort.
- Skip crunchy or sharp-edged foods. Chips, crackers, toast, and crusty bread can physically scrape the ulcer and reopen healing tissue.
- Switch to a gentle toothpaste. Toothpastes containing sodium lauryl sulfate (the ingredient that makes them foam) can irritate canker sores. Look for SLS-free options while you’re healing.
- Use a soft-bristled toothbrush. Brushing near the sore with a stiff brush can tear the tissue. Be thorough but gentle.
Over-the-counter oral gels that contain a numbing agent can also provide a temporary protective barrier. Apply them before meals to make eating less painful.
What the Healing Timeline Looks Like
Canker sore pain typically peaks in the first two to three days, then gradually improves. The ulcer itself usually closes within about two weeks without any treatment at all. Home remedies primarily shorten the painful phase and may knock a few days off the total healing time, but they won’t make a sore vanish overnight.
During healing, you’ll notice the sore shrink from the edges inward. The white or yellowish center will gradually be replaced by pink tissue. If a sore keeps growing after the first few days instead of improving, that’s worth paying attention to.
Preventing Sores From Coming Back
If you get canker sores repeatedly, a nutritional gap may be part of the picture. Vitamin B12 deficiency is one of the more common links. A randomized trial published in the Journal of the American Board of Family Medicine found that taking a daily sublingual B12 supplement (1,000 mcg) for six months significantly reduced canker sore recurrence. The striking part: it worked regardless of whether participants had low B12 blood levels to begin with. Deficiencies in iron and folate have also been associated with recurrent sores.
Beyond nutrition, common triggers include stress, lack of sleep, minor mouth injuries (biting your cheek, dental work), and hormonal shifts. Keeping a simple log of when sores appear can help you identify your personal pattern. Some people notice sores reliably follow a stressful week or a particular food, and avoiding that trigger reduces how often they show up.
Signs a Sore Needs Professional Attention
Standard canker sores are small (under 1 cm across) and shallow. Sores that are unusually large, deeply ulcerated, or spreading deserve a closer look from a dentist or doctor. The same goes for sores that haven’t started healing after two weeks, sores accompanied by a fever, or clusters of sores that keep returning in rapid succession. These patterns can occasionally point to an underlying condition that home treatment won’t address.