Most mouth ulcers heal on their own within 10 to 14 days, but the right combination of pain relief, protective barriers, and trigger avoidance can shorten that timeline and make the process far less miserable. The key is reducing irritation so your body’s natural healing process isn’t constantly interrupted.
What You’re Dealing With
The most common mouth ulcers (called minor aphthous ulcers) are small, round sores on the soft tissues inside your mouth: inner cheeks, tongue, gums, or the floor of your mouth. They’re not contagious and not caused by a virus. That 10-to-14-day window is the typical course without any treatment at all, so everything below is about speeding things up or making those days more bearable.
Larger ulcers, sometimes called major aphthous ulcers, can take up to a month to heal. And a rarer type appears as clusters of tiny sores that merge together, lasting anywhere from 10 days to over three months. If your ulcer is unusually large, keeps growing, or has stuck around for more than three weeks, that’s a different situation that needs a professional evaluation.
Rinses That Actually Help
A saltwater or baking soda rinse is the simplest, cheapest first step. Memorial Sloan Kettering Cancer Center recommends mixing 1 teaspoon of salt and 1 teaspoon of baking soda into 1 quart (4 cups) of water. You can also use just salt or just baking soda if that’s what you have. Rinse every four to six hours, swishing gently for 30 seconds before spitting. The salt draws fluid from swollen tissue, and the baking soda helps neutralize acids in your mouth that irritate the open sore.
Avoid mouthwashes that contain alcohol. They’ll sting on contact and can dry out the tissue around the ulcer, which slows healing rather than helping it.
Over-the-Counter Pain Relief
Numbing gels and pastes containing benzocaine are widely available at pharmacies and work by temporarily blocking nerve signals at the ulcer’s surface. Apply directly to the sore with a clean finger or cotton swab. The relief is real but short-lived, usually lasting 15 to 30 minutes, which makes them most useful right before eating.
Bioadhesive oral gels take a different approach. Rather than numbing the area, they form a thin protective film over the ulcer that shields exposed nerve endings from food, drinks, and the constant friction of your tongue and teeth. This coating sticks to the moist surface inside your mouth, though it does gradually wash away with saliva and eating. Reapply as needed.
For ulcers that are especially painful or slow to heal, pharmacists can recommend topical steroid pastes. These work by reducing the inflammation driving the pain and swelling. Triamcinolone in an oral paste base is one common option. Stronger prescription-strength steroids exist for stubborn cases, but most people won’t need them.
Honey as a Natural Option
Honey, particularly Manuka honey, has genuine clinical support for mouth sores. In a randomized controlled trial of children with chemotherapy-related oral ulcers, those treated with Manuka honey had significantly less severe sores and less pain than the control group. The honey’s thickness creates a natural protective layer over the ulcer, and its antibacterial properties help keep the wound clean.
To try this at home, dab a small amount of raw honey directly onto the ulcer a few times a day. It won’t taste bad, and even if the evidence comes from a specific clinical population, the mechanism (coating and protecting the sore) applies to ordinary mouth ulcers too.
Stop Irritating the Ulcer
This is the part most people overlook, and it matters as much as any treatment you apply. Every time something rough, acidic, or sharp hits that open sore, it restarts the inflammatory cycle and delays healing.
- Switch your toothpaste. Many toothpastes contain sodium lauryl sulfate (SLS), a foaming agent that can irritate delicate oral tissue. Research has shown that SLS-containing toothpaste increases the frequency of recurrent mouth ulcers. Look for an SLS-free toothpaste, which most pharmacies carry.
- Avoid acidic foods. Citrus fruits, tomatoes, vinegar-based dressings, and carbonated drinks all lower the pH in your mouth and sting on contact. Cut these out until the ulcer closes.
- Skip crunchy and sharp-edged foods. Chips, crusty bread, and raw vegetables can physically scrape the sore. Stick to softer foods during the worst days.
- Use a soft-bristled toothbrush. Brush carefully around the ulcer rather than over it.
Check for Nutritional Gaps
If you get mouth ulcers repeatedly, not just once in a while, a nutritional deficiency could be the underlying driver. A study of 273 patients with recurrent mouth ulcers found that about 21% were anemic, 20% had low iron levels, nearly 5% were deficient in vitamin B12, and about 3% were low in folic acid. These deficiencies impair your body’s ability to maintain and repair the mucosal lining inside your mouth.
You don’t need to start megadosing supplements based on a guess. A simple blood test can identify whether iron, B12, or folate is low. If one of these is the cause, correcting the deficiency often reduces or eliminates the ulcers entirely. This is especially worth investigating if you follow a restricted diet, eat very little red meat, or have heavy menstrual periods.
Common Triggers Worth Tracking
Beyond nutritional causes, mouth ulcers are frequently triggered by mechanical injury (biting your cheek, a sharp tooth edge, aggressive brushing), stress, hormonal changes, and food sensitivities. Some people notice ulcers after eating certain foods like chocolate, coffee, nuts, or wheat, though the specific triggers vary from person to person.
If ulcers keep coming back, it helps to keep a simple log of what you ate, how stressed you were, and where you are in your menstrual cycle (if applicable) in the days before each one appears. Patterns usually emerge within a few months.
Signs That Need Professional Attention
Most mouth ulcers are harmless and temporary, but certain features warrant a visit to your doctor or dentist. According to the Cleveland Clinic, you should seek evaluation if:
- A sore lasts longer than three weeks
- The ulcer is unusually large
- New sores keep appearing before old ones heal
- Sores develop on the outer part of your lips (which suggests a different diagnosis)
- Pain doesn’t improve with over-the-counter treatment
- The sore is painless (painless ulcers can occasionally signal something more serious)
- You also have a fever or diarrhea
Persistent or unusually behaving ulcers can sometimes be linked to autoimmune conditions, celiac disease, or rarely, oral cancer. A three-week threshold is the standard cutoff clinicians use to decide whether further investigation is needed.