Most canker sores heal on their own within two weeks, but the right treatments can cut pain almost immediately and shorten that timeline by several days. The fastest option available is a numbing gel you can buy at any pharmacy, which works within minutes. For actually speeding up healing, you have several proven choices depending on severity.
Numbing Gels for Immediate Pain Relief
If you need to eat, drink, or just stop hurting right now, an over-the-counter oral gel containing benzocaine is your quickest fix. These gels numb the sore on contact and typically last 30 to 60 minutes. You apply a small amount directly to the ulcer, and the pain fades within a couple of minutes. Look for products labeled for mouth sores or toothache pain at any drugstore. Reapply as needed throughout the day.
Numbing gels don’t make the sore heal faster. They just block the pain signal while your body does the actual repair work. That said, pain relief matters: a canker sore on your tongue or inner cheek can make eating miserable, and skipping meals slows recovery.
Treatments That Actually Speed Healing
If you want the sore gone sooner, not just numbed, you need something that reduces inflammation or protects the ulcer so tissue can regenerate faster.
Honey is one of the more surprising options with real evidence behind it. A randomized clinical trial found that applying honey to canker sores four times a day for five days significantly reduced ulcer size, pain, and redness compared to both a topical steroid and a protective paste alone. Honey has natural anti-inflammatory and antimicrobial properties. Use plain, unprocessed honey and dab it directly on the sore after meals and before bed. It stings briefly, then soothes.
Over-the-counter protective pastes create a barrier over the ulcer, shielding it from food, drinks, and your teeth. These won’t dramatically accelerate healing, but they reduce irritation that can make the sore worse or slow it down. Apply them after eating and before sleep for the best coverage.
Saltwater rinses are the simplest home remedy. Dissolve half a teaspoon of salt in a cup of warm water and swish for 30 seconds, two to three times a day. Salt draws fluid out of the inflamed tissue, which reduces swelling and helps clean the area. It will sting, but most people notice the sore feels better afterward.
When to Ask for a Prescription
For canker sores that are unusually large (bigger than a centimeter), extremely painful, or keep coming back, a doctor or dentist can prescribe a steroid mouth rinse. You swish the liquid around your mouth and spit it out. The steroid suppresses the immune overreaction causing the ulcer, which shrinks it faster than anything over the counter. One thing to know: using a steroid rinse can sometimes lead to a secondary fungal infection in the mouth, so it’s typically reserved for more severe cases.
Laser treatment is another option some dental offices now offer. A diode laser applied to the sore for under a minute can relieve pain almost immediately, sometimes during the session itself. In one clinical series, 90% of patients needed only a single treatment. The laser seals nerve endings and stimulates tissue repair. It’s not widely available everywhere, and it may not be covered by insurance, but if you get severe or frequent canker sores, it’s worth asking your dentist about.
Reducing How Often They Come Back
Getting rid of the current sore is only half the battle if you’re someone who gets canker sores regularly. One of the most effective prevention steps is switching to a toothpaste that doesn’t contain sodium lauryl sulfate (SLS), the foaming agent in most commercial toothpastes. A systematic review of clinical trials found that people using SLS-free toothpaste had significantly fewer ulcers, shorter episodes, and less pain compared to those using standard toothpaste. Check the ingredients on your tube. Several major brands now sell SLS-free versions.
Nutritional deficiencies are another common trigger. Research comparing people with recurrent canker sores to those without found that more than half of the canker sore group had deficiencies in iron, folate, or vitamin B12, compared to fewer than one in ten in the control group. If you get canker sores frequently, it’s worth having your levels checked. A simple blood test can identify whether supplementation might help break the cycle.
Other common triggers include acidic foods (tomatoes, citrus, vinegar-based dressings), physical trauma from braces or biting your cheek, stress, and hormonal changes. Keeping a simple log of what you ate and what was happening in your life before each outbreak can help you identify your personal triggers over time.
Make Sure It’s Actually a Canker Sore
Canker sores are sometimes confused with cold sores, but the two are very different. Canker sores appear inside the mouth, typically as a single round white or yellow sore with a red border. Cold sores (fever blisters) appear outside the mouth, usually around the border of the lips, and look like clusters of small fluid-filled blisters. Cold sores are caused by the herpes simplex virus and are contagious. Canker sores are not viral and can’t spread to other people.
If a sore inside your mouth hasn’t healed after three weeks, is growing instead of shrinking, comes with fever, or makes it genuinely difficult to swallow liquids, it may be something other than a standard canker sore and is worth getting evaluated.