Most canker sores heal on their own within one to two weeks, but the right treatment can cut pain significantly and speed up that timeline. Your best options range from simple saltwater rinses to over-the-counter numbing gels, protective patches, and, for severe or recurring sores, prescription steroid rinses. What works best depends on how painful the sore is and how often you get them.
Saltwater and Baking Soda Rinses
The simplest and cheapest place to start is a rinse you can make at home. The Mayo Clinic recommends dissolving 1 teaspoon of baking soda in half a cup of warm water, then swishing it gently over the sore. A basic saltwater rinse (about half a teaspoon of salt in the same amount of warm water) works similarly. Both help neutralize acids in your mouth that irritate the ulcer, and the mild antiseptic effect can keep the area cleaner while it heals.
These rinses won’t numb the pain or dramatically shorten healing time, but they’re a solid first line of defense, especially for mild sores. You can repeat them several times a day, particularly after meals.
Over-the-Counter Numbing Gels
Topical anesthetics containing benzocaine or lidocaine are the most popular OTC option for canker sore pain. You apply the gel, liquid, or paste directly to the sore, and the area goes numb within a minute or two. Relief is temporary, typically lasting 15 to 30 minutes, but it can make eating and drinking far more bearable.
Apply these products up to four times a day, and avoid eating or drinking immediately afterward so the medicine stays in contact with the sore longer. Products marketed specifically for canker sores (like Orajel or Anbesol) contain these same active ingredients. Children under two should not use benzocaine products.
Protective Patches and Pastes
If your sore sits in a spot that constantly rubs against your teeth or cheek, a physical barrier can help more than a rinse. Adhesive oral patches stick directly over the ulcer and shield it from friction and food. Most use a gel-forming polymer that adheres to wet tissue and stays in place for roughly an hour and a half before dissolving. Brands like Canker Cover and DenTek sell these over the counter.
Protective dental pastes work on a similar principle. You dab a small amount over the sore, and it forms a temporary coating. Some contain a mild numbing agent alongside the barrier, giving you both pain relief and protection in one step.
Honey as a Topical Treatment
Plain honey is surprisingly effective. A randomized clinical trial compared applying honey three times a day to using a standard prescription steroid paste (triamcinolone acetonide) on the same schedule. Both groups saw nearly identical results: ulcer size shrank by about 60% within the first few days, and both groups reached complete healing and total pain resolution by the final follow-up visit. Pain scores dropped by roughly 48% in each group during the early healing window.
If you want to try this, dab a small amount of honey directly onto the sore after meals and before bed. Keep it unprocessed if possible. Avoid eating or drinking for at least 20 minutes afterward to let it sit on the tissue.
Prescription Steroid Rinses
For large, intensely painful, or frequently recurring canker sores, a dentist or doctor may prescribe a medicated mouth rinse containing a corticosteroid. These rinses reduce the inflammatory response driving the ulcer, which shrinks the sore faster and eases pain more effectively than OTC options alone.
The typical routine is to swish a small amount in your mouth for about one minute, then spit it out. You do this four times a day: after each meal and before bed. The key detail that makes these rinses work well is avoiding all food and drink for at least 30 minutes afterward. That extended contact time is what lets the medication absorb into the tissue. Your prescriber may also combine the steroid with an antifungal agent to prevent oral yeast infections, a common side effect of prolonged steroid use in the mouth.
Chemical Cautery for Fast Relief
A prescription product called Debacterol uses a chemical solution to essentially cauterize the ulcer in a single application. In a pilot study, 80% of treated ulcers had completely disappeared and were pain-free by day six, compared to only about 30% in comparison groups at the same time point. All groups reached full healing by day 10, but the early pain relief is the real advantage. This is a one-time, in-office or at-home treatment applied with a small swab. It stings briefly during application, then the pain from the sore itself drops sharply.
Switching Your Toothpaste
If you get canker sores repeatedly, your toothpaste may be contributing. Sodium lauryl sulfate (SLS), a foaming agent in most toothpastes, can irritate oral tissue and trigger ulcers in susceptible people. A study tracking patients who switched to SLS-free toothpaste found that after three months, pain scores dropped significantly (from about 5 out of 10 to 3.8), and the number of outbreaks fell from an average of 2.4 episodes to 1.9 over the same period. The size of individual sores and how long each episode lasted didn’t change, but getting fewer, less painful outbreaks is a meaningful improvement for something as simple as switching toothpaste brands. Sensodyne, Biotene, and several other widely available brands are SLS-free.
Nutritional Deficiencies and Prevention
Deficiencies in B vitamins, folic acid, or iron show up in 18 to 28 percent of people with recurrent canker sores, compared to about 8 percent in the general population. That’s a notable gap, though it means most people with canker sores aren’t deficient at all. If you get sores frequently and also experience fatigue, pale skin, or tingling in your hands and feet, it’s worth having your levels checked with a simple blood test. Correcting a genuine deficiency can reduce how often sores appear. But taking extra supplements when your levels are already normal is unlikely to help.
Canker Sores vs. Cold Sores
Before you treat, make sure you’re treating the right thing. Canker sores and cold sores look different and appear in different places. Canker sores form inside the mouth, on the soft tissue of your cheeks, gums, tongue, or the floor of your mouth. They’re typically a single round sore, white or yellowish in the center with a red border. Cold sores (fever blisters) appear outside the mouth, usually on or around the lips, and look like a cluster of small fluid-filled blisters. Cold sores are caused by the herpes simplex virus and are contagious. Canker sores are not contagious and have no known viral cause.
This distinction matters because the treatments are completely different. Antiviral creams for cold sores won’t help a canker sore, and numbing gels designed for canker sores won’t address the viral infection behind a cold sore.
When a Sore Needs Professional Attention
Most canker sores resolve within two weeks without any treatment at all. A sore that persists beyond that two-week mark after you’ve removed any obvious irritants (a sharp tooth edge, an ill-fitting appliance) warrants a professional evaluation. Persistent oral ulcers can occasionally signal other conditions, and a biopsy is generally recommended for lesions that don’t heal in that timeframe. Sores that are unusually large, appear in clusters, come with fever, or make it difficult to eat or drink enough fluids also justify a visit sooner rather than later.