Most mouth sores heal on their own within two weeks, but you can speed up recovery and cut the pain significantly with a few simple treatments. The right approach depends on what type of sore you’re dealing with, so it helps to identify that first before reaching for a remedy.
Identify Your Mouth Sore First
The two most common mouth sores are canker sores and cold sores, and they require different treatments. The easiest way to tell them apart is location. Canker sores appear inside the mouth, on the inner cheeks, lips, or tongue. They look like a round white or yellow sore with a red border. Cold sores show up on the outside of the mouth, usually around the border of the lips, as a cluster of small fluid-filled blisters.
Canker sores are not contagious and don’t have a single known cause. They can be triggered by injury (biting your cheek, sharp food, dental work), stress, smoking, or deficiencies in iron, vitamin B12, or folate. Cold sores are caused by herpes simplex virus type 1 and are very contagious. Both types produce a tingling or burning sensation before the sore fully forms, which is your window to start treatment early.
Salt Water Rinse: The Best First Step
A salt water rinse is the simplest and most effective thing you can do at home. Mix one teaspoon of salt into eight ounces of warm water. If your mouth is especially tender, start with half a teaspoon for the first day or two. Swish gently for 30 seconds, then spit.
Salt water works through several mechanisms at once. It kills bacteria by pulling water out of their cells through osmosis. It shifts the pH of your mouth toward alkaline, creating an environment where harmful bacteria can’t thrive easily. And it promotes wound healing by encouraging the migration of cells involved in tissue repair. Rinse two to three times a day, especially after meals.
Over-the-Counter Pain Relief
Benzocaine gels (sold as Orajel and similar products) numb the sore on contact. They come in 10% and 20% concentrations, both available without a prescription. The relief is temporary, lasting roughly one to two hours, but it can make eating and drinking far more comfortable. Apply a small amount directly to the sore with a clean finger or cotton swab. Reapply as needed following the product’s label directions.
You can also find over-the-counter adhesive patches that cover the sore and protect it from food and friction while delivering medication. These work especially well for canker sores on the inner lip or cheek where they constantly rub against teeth.
Honey as a Healing Agent
Applying honey directly to a mouth sore is more than a folk remedy. In clinical trials, honey performed as well as the antiviral medication acyclovir for cold sores, with complete healing of herpetic lesions in about eight days compared to nine days for acyclovir. When honey was combined with acyclovir in children with oral herpes, sores disappeared in a median of three days versus six days with medication alone. Eating difficulty dropped from eight days to three.
Honey appears to have both antiviral properties and a protective effect on the lining of the mouth. Dab a small amount of raw honey onto the sore several times a day. It won’t sting the way some treatments do, which makes it a good option for children or anyone with a low pain tolerance.
Foods That Make Sores Worse
Certain foods won’t cause a mouth sore from scratch, but they can trigger outbreaks in people who are prone to them and will absolutely aggravate an existing sore. The main culprits are acidic and spicy foods: coffee, oranges, grapefruit, pineapple, and tomato-based sauces. Salty, abrasive foods like chips and pretzels can physically irritate the wound. Chocolate, cheese, nuts, and strawberries are also common triggers for some people.
While you have an active sore, stick to soft, mild foods. Yogurt, bananas, scrambled eggs, and lukewarm soups are gentle choices. Drink through a straw if the sore is on your inner lip.
Nutritional Deficiencies Worth Checking
If you get mouth sores repeatedly, the cause may be nutritional. Deficiencies in vitamin B12, folate, and iron are all linked to recurrent canker sores. The NHS lists mouth ulcers as a recognized symptom of B12 or folate deficiency anemia, alongside a sore or red tongue. If you notice you’re also unusually tired, pale, or short of breath, those deficiencies become more likely.
A simple blood test from your doctor can check all three levels. Addressing the deficiency often reduces or eliminates recurring sores. Good dietary sources of B12 include meat, fish, eggs, and dairy. Folate is found in leafy greens, beans, and fortified cereals. Iron-rich foods include red meat, lentils, and spinach.
When Prescription Treatment Helps
For severe or frequently recurring mouth sores, a doctor or dentist can prescribe a corticosteroid rinse. These are anti-inflammatory solutions you swish and spit, typically three times a day for several weeks. You hold the solution in your mouth for two to five minutes, then avoid eating or drinking for 15 minutes afterward. Response rates to prescription corticosteroid rinses range from 30% to 100% depending on the specific formulation and condition being treated.
For cold sores specifically, prescription antiviral medications can shorten outbreaks, especially when started at the first tingling sensation before blisters form.
Toothpaste and Prevention
You may have heard that switching to a toothpaste free of sodium lauryl sulfate (SLS), the foaming agent in most toothpastes, can prevent canker sores. The evidence is mixed. Some studies have found that removing potential irritants from toothpaste reduced the number and frequency of sores, while at least one well-designed study found no significant difference in ulcer patterns. It’s a low-risk experiment: if you get frequent canker sores, trying an SLS-free toothpaste for a few months costs nothing and may help.
Beyond toothpaste, basic prevention comes down to managing known triggers. Use a soft-bristled toothbrush to avoid scraping the inside of your mouth. Manage stress where you can. Avoid foods you’ve identified as personal triggers. If you have braces or a dental appliance with a sharp edge, ask your dentist to smooth it.
Signs a Mouth Sore Needs Medical Attention
The two-week mark is the critical threshold. If a mouth sore hasn’t healed within two weeks, schedule an appointment with your doctor or dentist. Most canker sores resolve well before that, even without treatment.
A few features can help distinguish a harmless sore from something more serious like oral cancer. Canker sores tend to be flat, painful, and surrounded by red, inflamed tissue. Oral cancers in their earliest stages are often painless and may have a small lump or bump beneath the surface you can feel with your tongue. Watch for a small spot that grows larger, a white patch that turns red, or a lesion that starts bleeding when it didn’t before. Any sore that keeps coming back in the exact same spot also warrants a professional evaluation.