Most canker sores heal on their own within one to two weeks, but the right treatments can cut that timeline in half and dramatically reduce pain in the meantime. The key is acting early: nearly every effective option works better when you start it at the first sign of a sore rather than waiting until it’s fully formed.
What You’re Dealing With
A canker sore is a shallow, open ulcer on the soft tissue inside your mouth. It typically looks yellow or white in the center with a red, inflamed border. It’s not patchy, textured, or bleeding. It just hurts, especially when food, drinks, or your tongue brush against it. Most are small (under a centimeter) and resolve within 7 to 14 days without treatment. The goal of every remedy below is to shorten that window and make the days in between more bearable.
Home Remedies That Actually Help
A warm saltwater rinse is the simplest first-line treatment you can start immediately. The salt draws fluid out of the inflamed tissue through osmosis, which reduces swelling and creates a less hospitable environment for bacteria. St. Jude Children’s Research Hospital recommends a specific alkaline rinse: 1 teaspoon of table salt and 1 teaspoon of baking soda dissolved in 4 cups of warm water. Swish gently for 30 seconds, then spit. Repeat several times a day, especially after meals.
Honey applied directly to the sore can also speed things along. It forms a protective barrier over the ulcer, keeps it moist, and has natural antimicrobial properties. Dab a small amount onto the dried sore a few times a day. Ice chips or cold water won’t accelerate healing, but they temporarily numb the area if you need relief before a meal.
Over-the-Counter Options Worth Trying
Topical gels and pastes containing a numbing agent like benzocaine provide fast pain relief by blocking nerve signals at the sore’s surface. Apply them directly to the dried ulcer before eating or whenever pain flares up. They won’t dramatically shorten healing time, but they make the process far more tolerable.
Protective mouth rinses designed for oral sores coat the ulcer and shield it from further irritation. This matters because repeated trauma from food, teeth, or your tongue is one of the biggest reasons canker sores linger. Any barrier you can place between the sore and the rest of your mouth gives tissue a better chance to repair itself.
Prescription Treatments That Speed Healing
If your canker sore is large, unusually painful, or you get them frequently, a prescription option can meaningfully accelerate recovery. A steroid paste applied directly to the dried ulcer two to four times daily reduces inflammation at the source. Starting it early in the sore’s development makes a noticeable difference in how quickly it resolves.
Chemical cauterization is another in-office option. Silver nitrate, applied by a dentist or doctor, was shown in clinical studies to produce more pain-free patients within just one day, though it doesn’t necessarily shorten the total healing time. A similar prescription treatment called Debacterol reduced pain significantly more than placebo by day 3 and resolved symptoms more effectively by day 6.
Dental Laser Treatment
Low-level laser therapy is the fastest clinical option available. A dentist directs a soft-tissue laser at the sore in a single brief session. The laser kills bacteria on the ulcer’s surface and stimulates the tissue underneath to repair itself. Pain relief is essentially immediate after the procedure, and the sore can heal within about two days, compared to the typical two-week timeline with home care alone. Not every dental office offers this, and it’s rarely covered by insurance, but if you’re dealing with a particularly painful or stubborn sore, it’s worth asking about.
Switch Your Toothpaste
If you get canker sores repeatedly, your toothpaste might be part of the problem. Sodium lauryl sulfate (SLS) is a foaming agent found in most commercial toothpastes, and it irritates the soft tissue lining your mouth. A systematic review in the Journal of Oral Pathology and Medicine found that switching to an SLS-free toothpaste significantly reduced the number of canker sores people developed. One study within that review was striking: participants went from an average of 14.3 ulcers over three months while using SLS-containing toothpaste down to just 5.1 ulcers after switching to an SLS-free version.
This won’t heal the sore you have right now, but it’s one of the simplest long-term changes you can make. Brands like Sensodyne, Biotene, and several others sell SLS-free formulas. Check the ingredients list on the back of the tube.
Avoid Making It Worse
While you’re waiting for a canker sore to heal, what you avoid matters almost as much as what you apply. Acidic foods like citrus, tomatoes, and vinegar-based dressings directly irritate the open tissue. Spicy food does the same. Crunchy foods like chips and crusty bread can physically scrape the sore and reset the healing clock. Stick to softer, bland foods until the sore closes over.
Alcohol-based mouthwashes are another common mistake. They sting on contact and can further dry out and irritate oral tissue. If you want to rinse, stick with the salt and baking soda solution or an alcohol-free antiseptic rinse.
When a Canker Sore Isn’t Just a Canker Sore
A typical canker sore is yellow or white, smooth in texture, and doesn’t bleed or discharge fluid. It may turn gray as it heals. If a mouth sore lasts longer than three weeks, keeps growing, bleeds, feels firm or lumpy, or comes with unexplained weight loss or difficulty swallowing, it needs professional evaluation. Oral cancers can initially look like a stubborn ulcer, and the distinguishing factor is often simply that the sore doesn’t resolve on a normal timeline. A doctor or dentist can perform a visual assessment and feel for abnormal tissue to rule out anything serious.