Most mouth ulcers heal on their own within 10 to 14 days, but you can speed up the process and reduce pain with a few targeted strategies. The key is minimizing irritation, keeping the area clean, and using the right topical treatments to create conditions where your tissue can repair itself faster.
What Determines How Fast Your Ulcer Heals
The size of the ulcer matters more than anything else. Standard mouth ulcers (the kind most people get) are small, round, and appear on soft tissue like the inner cheeks, lips, or the floor of the mouth. These typically resolve in 10 to 14 days without treatment. Larger ulcers, those exceeding about 1 centimeter in diameter, can take up to 6 weeks and sometimes leave a scar.
Everything you do to heal a mouth ulcer faster comes down to two goals: reducing inflammation and protecting the wound from further damage. The strategies below work on both fronts.
Saltwater Rinses
A warm saltwater rinse is one of the simplest and most effective things you can do. Salt promotes the migration of healing cells to wound sites and stimulates the production of collagen and other structural proteins your tissue needs to close the gap. Lab research published in PLOS ONE found that saline concentrations around 1.8 to 2.2% were most effective at accelerating this process.
To get that concentration at home, dissolve about one teaspoon (5 grams) of salt in a cup (250 ml) of warm water. Swish gently for 30 seconds, then spit. Repeat two to three times a day, especially after meals. It stings briefly, but it cleans the ulcer and creates an environment that discourages bacterial growth.
Over-the-Counter Pain Relief
Numbing gels containing benzocaine are widely available at pharmacies and work by temporarily blocking nerve signals in the tissue you apply them to. Dab a small amount directly on the ulcer before meals or whenever the pain is bothering you. The relief is short-lived, usually 15 to 30 minutes, but it makes eating and drinking much more manageable.
Protective pastes and patches serve a different purpose. Rather than numbing the ulcer, they form a barrier over it, shielding the raw tissue from food, drinks, and your teeth. Some products combine both a numbing agent and a protective coating. Either approach helps, and you can use them alongside saltwater rinses without any conflict.
Prescription Options for Stubborn Ulcers
If your ulcer is large, unusually painful, or keeps coming back, a doctor or dentist can prescribe a steroid dental paste. These pastes work by suppressing the inflammatory response at the ulcer site, which reduces swelling, pain, and redness while giving your tissue a better chance to heal. The paste is applied at bedtime so it stays in contact with the ulcer overnight, and depending on severity, you may need to apply it two or three times a day, ideally after meals.
For people who get frequent or severe ulcers, laser therapy is another option offered by some dental practices. Animal studies show laser-treated oral wounds reached nearly complete healing by day 7, compared to about 79% healing in untreated wounds over the same period. The treatment is quick, usually painless, and can provide immediate relief.
What to Eat and Avoid
Acidic and spicy foods don’t cause mouth ulcers, but they can make an existing one significantly worse and more painful. Citrus fruits, tomatoes, vinegar-based dressings, hot sauces, and sharp-edged foods like chips or crusty bread all irritate exposed tissue and can delay healing. The UK’s National Health Service specifically recommends eating soft foods and drinking cool beverages through a straw while an ulcer is active.
Good choices include yogurt, oatmeal, mashed potatoes, scrambled eggs, smoothies, and lukewarm soups. Anything soft, bland, and close to room temperature will let your ulcer heal without repeated aggravation.
Honey as a Topical Treatment
Applying a small amount of honey directly to a mouth ulcer is a folk remedy with some clinical backing. Honey has natural anti-inflammatory and antimicrobial properties, and clinical trials have tested topical honey applied three times daily for oral wounds. If you want to try it, dab a small amount of raw honey onto the ulcer after meals and before bed. It won’t work miracles, but it’s safe and may offer mild pain relief and a protective coating similar to commercial barrier pastes.
Nutritional Deficiencies That Cause Recurring Ulcers
If you get mouth ulcers frequently, the problem may not be local. It could be nutritional. A study of 273 patients with recurrent mouth ulcers found that roughly 21% had anemia, 20% had low iron levels, about 5% were deficient in vitamin B12, and nearly 3% were low in folic acid. These deficiencies impair your body’s ability to maintain and repair the mucous membranes lining your mouth.
Vitamin B12 deficiency in particular has a well-documented link to recurring ulcers. If you notice a pattern of ulcers appearing every few weeks, especially alongside fatigue, pale skin, or tingling in your hands and feet, a simple blood test can check your levels. Correcting the underlying deficiency often reduces or eliminates the ulcers entirely.
Preventing Future Ulcers
Beyond nutrition, a few practical habits reduce your risk. Avoid biting your cheeks or lips, and be careful with hard or sharp foods. If you notice ulcers tend to appear after dental work or after poking yourself with a toothbrush, switch to a soft-bristled brush and use gentler strokes.
Some people find that switching to a toothpaste free of sodium lauryl sulfate (SLS), the foaming agent in most toothpastes, helps reduce outbreaks. The clinical evidence here is mixed. A 2019 review found limited data to confirm the benefit, and one double-blind study reported no significant change in ulcer frequency, duration, or pain. Still, SLS-free toothpastes are inexpensive and widely available, so it’s a low-risk experiment if you’re dealing with persistent ulcers. Stress is another common trigger. While harder to control, it’s worth noting if your ulcers tend to cluster around high-pressure periods in your life.
When a Mouth Ulcer Could Be Something Else
A mouth ulcer that hasn’t healed after three weeks is no longer behaving like a normal ulcer. One of the key symptoms of mouth cancer is an ulcer that simply won’t go away. This doesn’t mean every slow-healing sore is cancerous, but it does mean it needs to be evaluated. Your doctor or dentist can examine the area and, if needed, take a small tissue sample (biopsy) to check for abnormal cells. Other signs to watch for include unexplained lumps, persistent red or white patches, and changes in how your mouth feels or functions.