Most mouth sores heal on their own within 10 to 14 days, but the right combination of home care and over-the-counter products can cut down pain significantly and may speed healing. What works best depends on the type of sore you’re dealing with, so it helps to know what you have before choosing a treatment.
Identify What You’re Dealing With
The two most common mouth sores are canker sores and cold sores, and they respond to different treatments. Canker sores (aphthous ulcers) appear inside the mouth on soft tissue like the inner cheeks, tongue, or floor of the mouth. They’re small, round, and usually white or yellowish with a red border. Cold sores show up on or around the lips, are caused by the herpes simplex virus, and tend to form clusters of fluid-filled blisters before crusting over.
Canker sores are far more common and are the type most people mean when they search for help with mouth sores. They can be triggered by minor injuries (biting your cheek, a sharp chip), stress, certain foods, hormonal changes, or nutritional deficiencies. Cold sores, because they’re viral, follow a different treatment path and respond best to antiviral medication rather than the topical remedies that work well for canker sores.
Saltwater and Baking Soda Rinses
A simple rinse is the cheapest, most accessible first step, and cancer centers like Memorial Sloan Kettering recommend it as a standard part of oral care for patients with mouth sores. The recipe is straightforward: mix 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 at the same ratio. Rinse every 4 to 6 hours, swishing gently for 30 seconds before spitting.
Salt draws fluid from the tissue around the sore, which can reduce swelling. Baking soda neutralizes acids in the mouth that irritate open sores. Neither will dramatically speed healing, but both make the sore less painful and create a cleaner environment for your mouth to repair itself.
Over-the-Counter Pain Relief
Numbing gels and pastes containing benzocaine or lidocaine are the go-to OTC options. They block nerve signals at the sore’s surface, which provides temporary but real relief, especially before eating. Apply a small amount directly to the sore, and avoid eating or drinking for at least 30 minutes afterward so the medication stays in contact with the tissue long enough to work.
Protective pastes that form a barrier over the sore can also help. These stick to the wet tissue inside your mouth and shield the ulcer from food, drinks, and your teeth. Some products combine a numbing agent with a protective coating, which addresses both pain and irritation at once.
Honey as a Topical Treatment
Topical honey has performed surprisingly well in clinical comparisons. In one trial, patients who applied honey to their canker sores four times a day for five days had better outcomes than those using a prescription steroid paste or a benzocaine-based product. The honey group saw greater reductions in ulcer size, fewer days of pain, and less redness, with statistically significant differences across all three measures.
Plain, unprocessed honey works for this purpose. Dab a small amount directly on the sore after meals and before bed. It stings briefly on contact but forms a soothing coating. Honey has natural antibacterial properties and helps maintain a moist wound environment, both of which support faster healing.
Prescription Options for Stubborn Sores
When canker sores are large, frequent, or slow to heal, prescription mouth rinses can change the course of the disease rather than just managing symptoms. Steroid-based rinses are the treatment of choice for recurrent canker sores. They work by calming the overactive immune response that drives the ulcer’s formation, which both reduces pain and increases healing rates.
Antimicrobial rinses containing chlorhexidine are another prescription option, though the standard version contains alcohol that can sting open sores. An alcohol-free formulation exists and is better suited for people with active ulcers. One important detail with chlorhexidine: it gets deactivated by toothpaste ingredients, so you need to wait at least 30 minutes after brushing before using it.
For either type of prescription rinse, contact time matters. You swish and spit rather than swallow, and you should avoid eating or drinking for at least 30 minutes afterward to let the medication do its work.
Laser Treatment at the Dentist
Some dental offices now offer diode laser treatment for canker sores. The procedure is quick, taking about 90 seconds per sore, and uses low-level laser energy directed at the ulcer without touching it. In clinical use, several patients experienced pain reduction during or immediately after the session. The laser essentially accelerates the healing process and can provide relief the same day. It’s worth asking your dentist about if you deal with canker sores frequently and other treatments haven’t been enough.
Nutritional Gaps That Fuel Recurrence
If you get canker sores repeatedly, a nutritional deficiency could be part of the picture. Deficiencies in iron, folate, or vitamin B12 show up in 18 to 28 percent of people with recurrent canker sores, compared to about 8 percent of healthy controls. Correcting the deficiency improves canker sores in some of those patients.
That said, the connection isn’t as strong as it’s sometimes portrayed. One study of 90 patients with recurrent canker sores found that only three had measurable hematologic abnormalities, and there were no significant differences in B12 or folate levels compared to healthy controls. A standard complete blood count is a reasonable starting point if your sores keep coming back, but routine testing for every vitamin isn’t necessarily warranted unless your doctor suspects a specific deficiency based on other symptoms.
What to Avoid While Healing
Acidic foods like tomatoes, citrus fruits, and vinegar-based dressings directly irritate open sores and can make them hurt far more. Spicy foods, crunchy or sharp-edged snacks, and very hot beverages do the same. Stick to soft, bland, cool foods while the sore is at its worst, typically the first 5 to 7 days.
You may have heard that switching to a toothpaste without sodium lauryl sulfate (SLS), the foaming agent in most toothpastes, can reduce canker sore frequency. The idea has been around for decades, but a 2019 review found there simply isn’t enough evidence to confirm that SLS-free toothpastes reduce how often sores appear, how long they last, or how much they hurt. One well-designed study found no significant change in ulcer patterns after switching. It’s a low-risk thing to try, but don’t count on it as a solution.
Healing Timelines by Severity
Minor canker sores, the type most people get, heal within 10 to 14 days without scarring. These are typically under a centimeter in diameter. Major canker sores are larger, deeper, and can take up to 6 weeks to heal. These sometimes leave a scar. A third type, called herpetiform ulcers (despite having nothing to do with herpes), produces clusters of tiny sores that can merge into larger irregular ulcers lasting up to 10 days.
If a mouth sore hasn’t healed after two weeks, is unusually large, keeps coming back, or is accompanied by fever, difficulty swallowing, or new sores appearing before old ones heal, that pattern points toward something that needs professional evaluation. Persistent white patches on the gums, cheeks, or tongue, particularly in smokers, can be a condition called leukoplakia that warrants a closer look from a dentist or doctor.