Most sores on the side of the tongue heal on their own within one to two weeks, but you can speed things up and cut the pain significantly with a few targeted steps. The side of the tongue is especially vulnerable because it rubs against teeth and braces constantly, making these sores common and slow to resolve without some intervention.
What’s Causing the Sore
Before treating it, it helps to understand what you’re dealing with. The three most likely culprits for a sore on the lateral tongue are traumatic ulcers, canker sores (aphthous ulcers), and occasionally a flare of an inflammatory condition like oral lichen planus.
Traumatic ulcers come from a specific, identifiable injury: biting your tongue, scraping it on a sharp tooth edge or filling, burning it on hot food, or irritation from braces or a retainer. They tend to appear right at the spot where the damage happened and heal once the source of irritation is removed.
Canker sores look slightly different. They’re round or oval with a yellowish-gray center and a red border. They show up without an obvious injury and often recur. Stress, hormonal shifts, certain foods (citrus, tomatoes, spicy dishes), and nutritional gaps can all trigger them. Viral infections, autoimmune conditions, and celiac disease are also linked to recurrent canker sores, so frequent outbreaks are worth mentioning to a doctor or dentist.
Salt Water Rinses: Your First Line of Defense
A warm salt water rinse is the simplest, cheapest, and most effective thing you can do starting right now. Mix 1 teaspoon of table salt into 8 ounces of warm water until it dissolves completely. Swish it around your mouth for 15 to 30 seconds, focusing on the sore side, then spit it out. Do this up to four times a day. If it stings too much, drop to half a teaspoon of salt.
Salt water draws fluid out of inflamed tissue, which reduces swelling, and it creates an environment that’s harder for bacteria to thrive in. It won’t numb the pain instantly, but it promotes faster healing and lowers the chance of a secondary infection.
OTC Pain Relief and Protective Gels
For immediate pain relief, look for an oral gel or ointment containing benzocaine at your pharmacy. Apply a small amount directly to the sore as needed, up to four times a day. The numbing effect kicks in within a minute or two and lasts long enough to eat or drink without wincing.
Protective oral pastes that form a barrier over the ulcer are another option. These stick to the sore and shield it from further irritation by food, teeth, and saliva. They work well at night when you can’t control whether your tongue presses against your teeth while you sleep. Some products combine a numbing agent with the protective barrier, which gives you both benefits at once.
Honey as a Natural Treatment
If you prefer a natural approach, honey is more than folk medicine. In a controlled study comparing honey to a standard prescription anti-inflammatory paste for traumatic tongue ulcers, honey-treated ulcers shrank faster at every checkpoint. By day 7, honey-treated ulcers had shrunk to roughly 0.5 mm from an original size of nearly 5 mm, while the prescription-treated ulcers were still over 3 mm. The honey group recovered fully by day 11, compared to day 14 for the prescription group.
To use it, dab a small amount of raw honey directly onto the sore a few times a day. It has natural antibacterial and anti-inflammatory properties, and its thick consistency helps coat and protect the area. Manuka honey is often recommended, but the study used natural forest honey, suggesting the benefit isn’t limited to one variety.
What to Avoid While It Heals
What you stop doing matters as much as what you start doing. Acidic foods and drinks (orange juice, tomatoes, coffee, soda) will irritate the sore and slow healing. Spicy food does the same. Very hot food and drinks can re-damage the tissue. Crunchy foods like chips and crackers can physically scrape the ulcer. Stick to soft, bland, room-temperature foods until the sore closes up.
Alcohol-based mouthwashes are another common irritant. They burn on contact and can dry out the oral tissue around the sore. Switch to an alcohol-free mouthwash or stick with salt water rinses during healing.
Switch Your Toothpaste
This is the single biggest change you can make if you get tongue sores repeatedly. Most mainstream toothpastes contain sodium lauryl sulfate (SLS), a foaming agent that strips the protective mucus layer inside your mouth and leaves the tissue underneath exposed and vulnerable.
In a clinical study, patients who switched from an SLS-containing toothpaste to an SLS-free one saw their canker sore frequency drop by about 70%. Every single participant in the study benefited from the switch. The average number of ulcers fell from roughly 18 over three months to just 5 after switching. Look for “SLS-free” on the label. Several brands market this specifically, and they’re available at most drugstores.
Check for Nutritional Deficiencies
Recurrent tongue sores can be your body flagging a nutritional gap. The deficiencies most closely linked to mouth ulcers are vitamin B12, folate (vitamin B9), iron, zinc, and vitamin C.
B12 supports tissue repair in the mouth. When levels are low, the lining of your tongue and cheeks heals poorly, and sores keep coming back. Iron deficiency reduces oxygen delivery to oral tissue, which can cause tongue soreness even without a visible ulcer, and in more severe cases leads to a smooth, red, inflamed tongue. Folate deficiency triggers oral inflammation and cracking at the corners of the lips alongside ulcers. Zinc deficiency slows wound healing directly, so existing sores linger longer and new ones appear more often. Vitamin C deficiency weakens blood vessels and collagen production, making gums bleed easily and ulcers heal slowly.
If you get tongue sores more than a few times a year, a simple blood test can check these levels. Correcting a deficiency often reduces or eliminates the recurrence entirely.
When a Sore Needs Professional Attention
Most tongue sores resolve within 10 to 14 days. If yours hasn’t started improving after two weeks, or if it’s getting larger rather than smaller, that needs professional evaluation. A dentist or doctor may prescribe a compounded medicated mouthwash that typically combines a numbing agent, an anti-inflammatory, and sometimes an antibiotic or antifungal, depending on what’s causing the sore. You swish it around and spit it out, and it targets multiple aspects of the problem at once.
Other signs that warrant a visit: a sore that keeps coming back in the exact same spot (which can indicate a sharp tooth edge that needs smoothing), a sore accompanied by fever or swollen lymph nodes, white or red patches surrounding the ulcer, or any sore that feels hard or has raised edges. A painless ulcer on the side of the tongue that doesn’t heal is particularly worth getting checked, since persistent, non-healing lateral tongue ulcers are one of the things oral cancer screenings look for.
A Quick Healing Plan
- Days 1 through 3: Salt water rinses four times daily, benzocaine gel before meals, honey applied between meals. Avoid acidic, spicy, and crunchy foods.
- Days 3 through 7: Continue rinses. Pain should be noticeably decreasing. The sore’s edges should be shrinking inward.
- Days 7 through 14: The sore should be nearly or fully closed. If it’s still the same size or growing, schedule a dental or medical appointment.
- Ongoing prevention: Switch to SLS-free toothpaste, address any nutritional deficiencies, and ask your dentist to check for sharp tooth edges or poorly fitting dental work at your next visit.