Most gum sores heal on their own within one to three weeks, but the right care can reduce pain and speed recovery. The approach depends on what type of sore you’re dealing with and how severe it is. Here’s what works, what to watch for, and when a sore needs professional attention.
Identify What You’re Dealing With
The two most common types of mouth sores look and behave differently, and they require different care.
Canker sores (aphthous ulcers) form only inside the mouth, typically on the inner cheeks, lips, or tongue. They appear as a single round white or yellow sore with a red border. They’re not contagious and have no definitive known cause, though they can be triggered by injury, stress, smoking, or deficiencies in folic acid, iron, or vitamin B12.
Cold sores (fever blisters) show up on the outside of the mouth, usually around the border of the lips, as patches of small fluid-filled blisters. They’re caused by herpes simplex virus type 1 (HSV-1) and are contagious. Cold sores require antiviral treatment rather than the wound-care strategies that help canker sores, so it’s worth knowing the difference before choosing a remedy.
Gum sores can also result from irritation from braces or dentures, burns from hot food, or accidental biting. These traumatic sores heal similarly to canker sores once the source of irritation is removed.
Salt Water Rinses
A salt water rinse is the simplest and most widely recommended first step. Mix half a teaspoon of salt into a cup of warm water, swish gently for 30 seconds, and spit. Doing this two to three times a day helps keep the area clean, reduces bacteria around the sore, and draws out fluid that contributes to swelling. It won’t taste pleasant, but most people notice less tenderness within a day or two of consistent rinsing.
Over-the-Counter Pain Relief
If a gum sore is making it hard to eat or talk, a topical oral gel containing benzocaine can help. Benzocaine is a local anesthetic that numbs the tissue on contact, providing temporary relief that typically lasts long enough to get through a meal. You’ll find it in most pharmacies labeled for mouth pain. Apply a small amount directly to the sore with a clean finger or cotton swab.
For sores that are visibly inflamed and swollen, look for an oral paste containing a mild steroid designed for use inside the mouth. These reduce the inflammatory response in the tissue, which can shorten healing time for larger or more painful canker sores. Both types of products are available without a prescription.
Honey as a Healing Aid
Applying a small amount of honey directly to an oral sore is more than a folk remedy. A systematic review of 13 studies found that honey reduced either the severity or the duration of oral ulcers compared to control groups in 12 of those studies. Honey creates a protective barrier over the sore, has natural antibacterial properties, and supports tissue repair. Regular raw honey has the most clinical support for oral use. Manuka honey, despite its reputation for wound healing, hasn’t been well tested in clinical trials for mouth sores specifically, and one study noted adverse effects with its use in the mouth.
To try it, dab a small amount of honey onto the sore a few times a day, ideally after eating and rinsing. Avoid eating or drinking for several minutes afterward so it stays in place.
What to Avoid While Healing
Certain foods and habits will irritate an open sore and slow recovery. Acidic foods like citrus, tomatoes, and vinegar-based dressings sting on contact and can worsen inflammation. Spicy foods, crunchy chips, and very hot drinks all do the same. Stick to softer, cooler, and blander foods until the sore closes.
Some limited evidence has explored whether the foaming agent in most toothpastes, called sodium lauryl sulfate (SLS), contributes to recurrent canker sores. A 2019 review of the available studies found there wasn’t enough data to confirm that switching to SLS-free toothpaste reduces sore frequency, duration, or pain. That said, if you notice sores developing frequently and you want to experiment, SLS-free toothpastes are easy to find and won’t hurt to try.
How Long Healing Takes
Not all canker sores are created equal, and healing time varies significantly by size.
- Minor canker sores are the most common type, smaller than a centimeter across (about the size of a pea or smaller). These heal within a few weeks and don’t leave scars.
- Major canker sores are larger than a centimeter, extremely painful, and often leave scars. These can take months to fully heal and are more likely to need professional treatment.
- Herpetiform canker sores are rare. They appear as clusters of tiny pinpoint sores rather than a single ulcer. Despite looking alarming, they typically heal within about two weeks without scarring.
If you’re treating a minor sore with salt water rinses and topical relief, you should notice improvement within the first week and full healing by weeks two or three.
Nutritional Gaps That Cause Recurring Sores
If gum sores keep coming back, the problem may not be local. It could be nutritional. Deficiencies in vitamin B12, folic acid, and iron are all established triggers for recurrent canker sores. Low B12 in particular is linked to glossitis (a painful, swollen tongue), increased sensitivity of the mouth lining, and ulcerative lesions throughout the oral cavity.
B12 deficiency is especially common in vegetarians, vegans, older adults, and anyone with digestive conditions that impair absorption. A simple blood test can check your levels. If you’re found to be deficient, oral supplementation is the typical starting point. Eating more B12-rich foods like eggs, dairy, meat, and fortified cereals can help maintain levels over time. If you’re getting canker sores more than a few times a year, it’s worth asking your doctor to check for nutritional deficiencies rather than just treating each sore individually.
Laser Treatment for Stubborn Sores
For sores that are large, extremely painful, or recurring frequently, some dental offices offer laser treatment. The laser essentially cauterizes the open wound, which seals it off from further irritation and infection. A single treatment can reduce healing time to roughly two days, compared to the weeks a sore might take on its own. The procedure is quick and provides near-immediate pain relief for most patients. It’s not necessary for a typical minor sore, but for people who deal with major canker sores regularly, it can be a significant quality-of-life improvement.
Red Flags Worth Watching
Most gum sores are harmless and temporary, but a sore that doesn’t heal deserves attention. Oral cancer can present as a mouth sore that persists, a white or reddish patch inside the mouth, a lump or growth, unexplained mouth or ear pain, or difficulty swallowing. The key distinction is duration: if any sore or unusual patch in your mouth persists for more than two weeks without improvement, it needs evaluation. Painless sores that don’t heal are actually more concerning than painful ones, since canker sores hurt precisely because they’re inflammatory, not cancerous.