Most mouth ulcers (canker sores) heal on their own within a few weeks, but you can speed up recovery and cut the pain significantly with the right combination of home care and over-the-counter treatments. Minor ulcers, the most common type, are smaller than a centimeter across and typically resolve in seven to 14 days without scarring. Larger ones can linger for weeks or even months. Here’s what actually works to get rid of them faster.
Know Which Type You’re Dealing With
Not all mouth ulcers behave the same way. Minor ulcers are the ones most people get: small, round sores less than a centimeter wide that show up on the inner cheeks, lips, or tongue. They hurt for a week or so and then disappear without leaving a mark.
Major ulcers are larger than a centimeter, extremely painful, and can take months to heal. They often leave scars on the tissue. Herpetiform ulcers are a third type, appearing as clusters of up to 100 tiny sores (each just one to three millimeters) scattered across the mouth. Despite the name, they’re not caused by herpes. If you’re dealing with a single small sore, home treatment is usually enough. Multiple large or long-lasting sores call for a different approach.
Salt Water Rinse: The Simplest Fix
A warm salt water rinse is the fastest thing you can do right now. Dissolve about half a teaspoon of table salt in a cup of warm water and swish it around your mouth for 30 seconds before spitting it out. Research from the National Dental Centre Singapore found that a roughly 7 percent salt concentration improved wound healing effectiveness, and rinsing helps neutralize the oral environment so the ulcer can repair itself. You can repeat this several times a day, especially after meals.
Don’t rub salt directly on the sore. That causes unnecessary tissue damage and intense pain without any added healing benefit over a rinse.
Topical Honey as a Treatment
Applying honey directly to the ulcer is one of the more effective home remedies, and the evidence behind it is surprisingly strong. In a clinical comparison, patients who dabbed honey on their ulcers four times a day for five days saw better results than those using a standard numbing paste (containing benzocaine) or a prescription-strength steroid. The honey group had faster reduction in ulcer size, fewer days of pain, and less redness. Honey has natural antimicrobial properties and supports the healing environment of oral tissue. Use raw, unprocessed honey if possible. Apply a small amount with a clean finger or cotton swab and try not to eat or drink for a few minutes afterward.
Over-the-Counter Pain Relief
Numbing gels and pastes containing benzocaine are widely available at pharmacies and provide temporary pain relief by dulling the nerve endings around the sore. They won’t speed healing much, but they make eating and talking less miserable. Apply them directly to the ulcer before meals for the best effect.
Antiseptic mouth rinses designed for oral sores can also help keep the area clean and reduce the risk of a secondary bacterial infection slowing down recovery. Look for alcohol-free versions, since alcohol-based rinses tend to sting and can irritate the ulcer further.
When You Need a Prescription
For ulcers that are large, extremely painful, or keep coming back, a doctor or dentist may prescribe a topical corticosteroid. These come in cream, gel, or ointment form and work by reducing the inflammatory response that’s driving the pain and swelling. They’re most effective when applied early, ideally as soon as you notice a new ulcer forming. Prescription options are stronger than anything available over the counter and can shorten healing time for major ulcers significantly.
Fix the Nutritional Gaps Behind Recurring Ulcers
If you keep getting mouth ulcers, a nutritional deficiency may be the underlying cause. Three vitamins are most closely linked to recurrent outbreaks: B12, folate, and vitamin C.
Vitamin B12 deficiency is one of the most common culprits. Adults generally need around 1,000 micrograms daily through supplementation if their levels are low, though the exact dose depends on whether the deficiency stems from diet or an absorption problem. Foods rich in B12 include meat, fish, eggs, and dairy.
Folate deficiency also drives recurrent ulcers. The standard recommended intake is 400 micrograms daily for most adults, rising to 600 to 800 micrograms during pregnancy. Leafy greens, legumes, and fortified grains are good dietary sources.
Vitamin C plays a role too, with mild deficiencies responding to 100 to 500 milligrams daily. If your ulcers are a chronic problem and you can’t pinpoint a trigger, ask your doctor to check your levels of these nutrients through a simple blood test.
Switch Your Toothpaste
Many common toothpastes contain sodium lauryl sulfate (SLS), a foaming agent that irritates the oral lining and is a known trigger for mouth ulcers in susceptible people. Clinical trials have specifically tested whether switching to SLS-free toothpaste reduces outbreaks, and the link is well-established enough that it’s one of the first recommendations dentists make for patients with recurrent ulcers. Check your toothpaste’s ingredients list. If SLS is there and you’re getting ulcers regularly, try an SLS-free alternative for at least eight weeks to see if the frequency drops.
Avoid Triggers That Slow Healing
While your ulcer is active, certain foods and habits will make it worse or delay healing. Acidic foods like citrus, tomatoes, and vinegar-based dressings directly irritate the exposed tissue. Spicy foods do the same. Crunchy or sharp-edged foods like chips, crackers, and crusty bread can physically reopen the wound.
Stress is another well-documented trigger. Many people notice ulcers appearing during high-stress periods, and the connection isn’t just anecdotal. Stress hormones affect immune function in the oral mucosa, making tissue more vulnerable to breakdown. You can’t always eliminate stress, but recognizing the pattern helps you start treatment earlier.
If a rough or broken tooth edge keeps rubbing against the same spot inside your mouth, that mechanical irritation can cause ulcers to form repeatedly in the same location. A dentist can smooth down the offending edge in minutes.
Red Flags to Watch For
A mouth ulcer that doesn’t heal within two weeks deserves professional evaluation. Persistent sores that won’t close are one of the primary warning signs of oral cancer, along with white or reddish patches inside the mouth, unexplained lumps, loose teeth, ear pain, or difficulty swallowing. None of these symptoms automatically mean cancer, but any of them lasting beyond two weeks should be assessed by a doctor or dentist. The same applies to ulcers that are unusually large, spreading, or accompanied by fever.