Most mouth ulcers heal on their own within two weeks, but the right topical treatment can cut pain significantly and speed that timeline. Your options range from over-the-counter numbing gels you can pick up today to prescription-strength rinses for stubborn or severe sores.
Over-the-Counter Gels and Rinses
The fastest relief comes from topical products applied directly to the ulcer as soon as it appears. Three active ingredients dominate the pharmacy shelf:
- Benzocaine (found in Anbesol, Orabase, Zilactin-B) numbs the sore on contact. It’s the most widely available option and works well for pain that flares up during meals or brushing.
- Hydrogen peroxide rinses (Orajel Antiseptic Mouth Sore Rinse, Peroxyl) clean the ulcer and reduce bacteria around it, which can help prevent secondary irritation.
- Fluocinonide (Lidex, Vanos) is a steroid paste that reduces inflammation. Some formulations are available over the counter, though stronger versions need a prescription.
These products come as pastes, creams, gels, and liquids. Pastes and gels tend to stick to the ulcer longer, giving the active ingredient more contact time. For best results, dry the area gently with a tissue before applying, and avoid eating or drinking for at least 15 to 20 minutes afterward.
Simple Home Remedies
A warm saltwater rinse is the simplest and most commonly recommended home treatment. Dissolve about half a teaspoon of salt in a cup of warm water and swish it around your mouth a few times a day. Salt water draws fluid out of the inflamed tissue, which reduces swelling and helps keep the area clean. It stings briefly on contact but tends to feel better afterward.
Baking soda works on a similar principle. Mixing a small amount with water to form a paste and dabbing it on the ulcer can help neutralize acids in the mouth that irritate the sore. Some people alternate between saltwater rinses and baking soda applications throughout the day.
When Ulcers Need Prescription Treatment
Topical corticosteroids are the first-line medical treatment for mouth ulcers that are large, extremely painful, or keep coming back. These reduce inflammation and pain, though they don’t prevent future outbreaks. Your doctor or dentist might prescribe a steroid paste you apply directly to the sore, or a steroid tablet you dissolve in water and use as a rinse, typically swishing for about four minutes at a time.
For multiple ulcers or widespread mouth pain, a compounded prescription rinse (sometimes called “magic mouthwash”) combines several ingredients: a numbing agent, an antacid to help the solution coat the tissue, and often an antihistamine for additional pain relief. The exact formula varies based on what’s causing the ulcers and how severe they are.
Chlorhexidine mouthwash, available by prescription, can reduce the severity and pain of ulcers, though like corticosteroids, it doesn’t prevent recurrence. For severe cases that don’t respond to anything topical, oral corticosteroids or other systemic medications may be necessary.
Vitamin B-12 for Recurring Ulcers
If you get mouth ulcers repeatedly, a vitamin B-12 supplement may help. A randomized, placebo-controlled study found that patients who took sublingual B-12 daily for six months had significantly fewer ulcers, less pain, and shorter outbreaks by the five- and six-month mark. Notably, this benefit appeared regardless of whether their B-12 blood levels were low to begin with, suggesting the effect isn’t just about correcting a deficiency.
What to Avoid While Healing
What you keep away from the ulcer matters almost as much as what you put on it. Acidic foods and drinks are the biggest culprits for worsening pain: citrus fruits, tomatoes, strawberries, fizzy drinks, and alcohol all lower the pH in your mouth and aggravate the exposed tissue. Spicy and salty foods irritate the delicate lining directly.
Texture matters too. Hard, crunchy, or sharp foods like crusty bread, chips, and raw vegetables can physically scrape the ulcer and delay healing. Stick to softer foods while the sore is active.
Your toothpaste is also worth checking. Many brands contain sodium lauryl sulfate (SLS), a foaming agent that can be harsh on mouth tissue. One study found that switching to an SLS-free toothpaste reduced the number, pain, and recurrence of ulcers. If you get frequent sores, this is one of the easiest changes to try.
How Long Healing Takes
Minor mouth ulcers, the most common type, are smaller than a centimeter across (about the size of a pea). Pain typically improves within a few days, and the ulcer itself heals within two weeks without scarring, even without treatment. Topical products mostly compress that timeline and make the painful days more bearable.
Major ulcers, those larger than a centimeter, are a different experience. They’re significantly more painful, can take months to heal, and often leave scars. These are the ones most likely to need prescription-strength treatment. If an ulcer hasn’t started improving after two weeks, is unusually large, or comes with fever, it’s worth having a doctor or dentist take a look to rule out other causes.