Most mouth sores heal on their own within two weeks, but the right combination of treatments can cut that time shorter and reduce pain significantly along the way. What works best depends on whether you’re dealing with a canker sore, a cold sore, or irritation from a bite or burn, since each responds to different approaches.
First, Identify What You’re Dealing With
The two most common mouth sores look and behave differently, and treating one like the other won’t help. Canker sores appear inside the mouth, usually on the inner cheeks, lips, or tongue. They’re typically a single round white or yellow sore with a red border. Cold sores (fever blisters) show up outside the mouth, generally around the border of the lips, and appear as clusters of small fluid-filled blisters. If your sore is inside your mouth with a white center, you almost certainly have a canker sore. The treatments below focus primarily on canker sores and general mouth irritation, since those are what most people are searching for.
Saltwater Rinse: Your Best First Step
A warm saltwater rinse is the simplest and most effective thing you can do immediately. Salt water works as a mild antiseptic, removing bacteria from the sore and reducing inflammation. It also stimulates the cells responsible for tissue repair (gingival fibroblasts), which is why dentists have recommended it for centuries.
Dissolve about half a teaspoon of table salt in a cup of warm water. Swish it gently around the sore for 15 to 30 seconds, then spit. Repeat two to three times a day, especially after meals. It will sting briefly on contact, but that fades quickly. This alone can noticeably speed healing and keep a minor sore from getting worse.
Over-the-Counter Pain Relief
Topical numbing gels containing benzocaine are the go-to for immediate pain relief. Apply a small amount directly to the sore up to four times a day. These products won’t dramatically speed healing, but they make eating and talking bearable while your body does the repair work. Look for gels marketed specifically for oral use at any pharmacy.
Antiseptic rinses containing hydrogen peroxide (diluted, sold pre-mixed for oral use) can also help keep the area clean and prevent secondary infection, which is one of the main things that slows healing down.
Honey as a Topical Treatment
Applying honey directly to a canker sore is more than a folk remedy. A clinical trial comparing honey-based treatment to a prescription corticosteroid paste found the two performed similarly: both groups saw significant pain reduction by day two, and average healing time was about five days in each group. If you don’t have access to a prescription option, dabbing a small amount of honey on the sore a few times a day is a reasonable alternative. Raw or medical-grade honey is preferable to processed varieties.
When to Ask About Prescription Options
For sores that are especially large or painful, a prescription corticosteroid dental paste can reduce inflammation at the site and speed tissue repair. The paste is applied in a thin layer directly over the sore, pressed gently until a film develops. You don’t rub it in. The best time to apply it is at bedtime, so the medication stays in contact with the sore overnight. For more severe cases, applying it two or three times daily after meals may be necessary.
If you haven’t seen meaningful improvement within seven days of using a corticosteroid paste, that’s a signal to follow up with your dentist or doctor. For severe or frequently recurring sores, some providers offer laser therapy, which can reduce pain and accelerate healing in a single visit.
What Slows Healing Down
Certain habits make mouth sores worse or drag out the healing process. Acidic foods (citrus, tomatoes, vinegar-based dressings) and spicy foods directly irritate open sores and can reset the healing clock. Crunchy or sharp-edged foods like chips and crackers risk physically reopening the wound. Alcohol-based mouthwashes, while they feel like they’re “cleaning” the area, can burn damaged tissue and delay recovery. Switch to an alcohol-free rinse or plain saltwater while you’re healing.
One factor many people overlook is their toothpaste. Sodium lauryl sulfate (SLS), the foaming agent in most toothpastes, has been linked to canker sore outbreaks. In a clinical trial of 90 participants, those who used SLS-free toothpaste reported their canker sores didn’t last as long and caused less pain compared to periods when they used standard toothpaste. If you get canker sores regularly, switching to an SLS-free brand is one of the simplest changes you can make.
Nutritional Gaps That Cause Recurring Sores
If mouth sores keep coming back, the problem may not be in your mouth at all. Vitamin B12 deficiency is one of the most well-documented nutritional causes of recurrent oral ulcers. Deficiencies in other B vitamins (B1, B2, B6), folic acid, iron, and zinc have also been linked to chronic mouth sore problems. Iron deficiency in particular can cause pale oral membranes and a chronic burning sensation alongside ulcers.
A simple blood test can identify these deficiencies. If you’re vegetarian or vegan, have digestive conditions that affect nutrient absorption, or eat a limited diet, you’re at higher risk. Correcting the underlying deficiency often dramatically reduces how often sores appear.
A Sore That Won’t Heal Is Different
Most mouth sores, even untreated, resolve within two weeks. A sore that persists beyond that window after any obvious irritant (a sharp tooth edge, a bite, a burn) has been addressed needs professional evaluation. The standard guideline is that any oral lesion lasting more than two weeks warrants a closer look, potentially including a biopsy, to rule out less common causes. This is especially true for sores that are painless, hard-edged, or growing, since those characteristics are less typical of ordinary canker sores.