Most tongue ulcers are canker sores that heal on their own within two to three weeks. But you can speed that process up and cut the pain significantly with a combination of home care, over-the-counter products, and smart food choices. If an ulcer hasn’t healed after three weeks, that’s the point where it needs professional evaluation.
Numb the Pain Quickly
For immediate relief, look for an over-the-counter oral gel containing benzocaine at your pharmacy. Apply a small amount directly to the ulcer up to four times a day, and don’t use it for more than two consecutive days without checking with a doctor or dentist. These gels create a temporary numbing film over the sore, making it easier to eat and talk. You’ll find them in the oral care aisle, often marketed for toothaches or canker sores.
If you don’t have benzocaine gel on hand, holding a small ice chip against the ulcer can dull the nerve endings enough to get through a meal.
Salt Water Rinses Still Work
A warm salt water rinse is one of the simplest and most effective things you can do. Mix 1 teaspoon of table salt and 1 teaspoon of baking soda into 4 cups of warm water. Swish a mouthful around for 15 to 30 seconds, then spit. You can repeat this several times a day, especially after meals. The salt helps draw fluid out of the swollen tissue, and the baking soda keeps the environment slightly alkaline, which is gentler on the raw surface than the naturally acidic conditions in your mouth.
Foods That Slow Healing
What you eat while the ulcer is open matters more than most people realize. Alcohol, fizzy drinks, and citrus fruits are the worst offenders. Acidic foods lower the pH in your mouth, which disrupts the protective proteins coating your oral tissue and leaves the ulcer more exposed. Strawberries and tomatoes are two foods people rarely suspect, but both are acidic enough to irritate an open sore.
Spicy and heavily salted foods irritate the delicate lining directly. And texture counts too: anything hard, crunchy, or sharp (think crusty bread, tortilla chips, raw carrots) can physically scrape the ulcer and reopen it. Stick to soft, cool, bland foods while you’re healing. Yogurt, smoothies, scrambled eggs, and mashed potatoes are all safe bets.
Honey as a Topical Treatment
Dabbing a small amount of honey directly onto the ulcer is a home remedy with some clinical backing. Honey has natural antibacterial properties and creates a protective coating over the sore. In clinical research, medical-grade honey applied to oral ulcers three times daily has been studied as a treatment to reduce both severity and pain. Swish it gently around the area for about a minute before swallowing. Use raw or medical-grade honey rather than processed varieties, which have fewer active compounds.
Prescription Options for Stubborn Ulcers
If over-the-counter options aren’t cutting it, a dentist or doctor can prescribe a steroid dental paste. This is a thick paste you apply with a cotton swab after meals and at bedtime, pressing it gently onto the ulcer to form a smooth film. The key is not to rub or spread it, which makes it crumble. The steroid reduces inflammation and helps the tissue repair itself faster. These pastes are typically reserved for ulcers that are especially large, painful, or slow to heal.
Why Some People Get Them Repeatedly
If tongue ulcers keep coming back, the cause is often something happening inside your body rather than a surface-level irritation. Deficiencies in vitamin B12, folate, and iron are well-established triggers. These nutrients are essential for maintaining healthy oral tissue, and when levels drop, the lining of your mouth becomes fragile and prone to breaking down. A simple blood test can identify whether a deficiency is driving recurrent ulcers.
There was a period when many dentists recommended switching to toothpaste free of sodium lauryl sulfate (SLS), a foaming agent thought to irritate oral tissue. A 2019 review found there wasn’t enough evidence to confirm that SLS-free toothpaste actually reduces how often ulcers appear, how long they last, or how much they hurt. It’s a low-risk experiment if you want to try it, but don’t expect a dramatic difference.
Certain systemic conditions also cause recurring oral ulcers. Celiac disease can produce mouth sores as one of its less obvious symptoms. Behçet’s disease, a rare condition involving widespread blood vessel inflammation, often first shows up as painful mouth ulcers that look like canker sores, heal in one to three weeks, and then return. People with Behçet’s typically also develop eye inflammation, skin rashes, or genital sores over time.
When an Ulcer Needs Professional Attention
The three-week mark is the dividing line. Most canker sores, even large ones, resolve within that window. An ulcer that persists beyond three weeks needs to be examined by a doctor or dentist, because the short list of things that don’t heal includes oral cancer. The difference is often visible: cancerous lesions tend to be painless in their early stages, may have hardened or raised edges, and sometimes appear as white or red patches rather than a clean round sore. But appearance alone isn’t reliable enough to tell them apart, which is why any ulcer that lingers past three weeks warrants a professional look.