11 Evidence-Backed Ways To Help Canker Sores Heal Faster

The oldest first move, with reasonable lab support

The salt water rinse is the canker sore equivalent of a hug. It is gentle, low-risk, recommended by almost every dental practice in the world, and it makes the sore feel just a little bit better while it heals.

The most common preparation is about a teaspoon of salt dissolved in a cup of warm water. A thirty-second swish, then spit. Repeating it a few times a day, especially after meals, helps rinse the area clean and reduces some of the local irritation that keeps the sore feeling raw. The American Dental Association's MouthHealthy resource lists saline rinses among the home measures patients can use during a flare.

The case for honesty: large randomized trials comparing salt water rinses to placebo for canker sore healing are limited. The supporting evidence is more mechanistic, including a 2016 in vitro study published in PLOS One that found brief saline exposure promoted the migration of human gingival fibroblasts, a step that matters in oral wound healing. That is not the same as a head-to-head clinical win, but it does suggest the rinse is doing something useful, not just feeling like it is.

Practical detail: warm, not hot. If it stings briefly on contact with the sore, that is normal. If you are watching sodium intake, the small amount that ends up swallowed is not meaningful, but spitting most of it is the right move regardless.

The home remedy with surprisingly strong clinical backing

This one is the quiet overachiever of the canker sore world. A small dab of medical-grade or pure manuka honey applied directly to the ulcer with a clean cotton swab, three to four times a day, has performed remarkably well in clinical trials, occasionally outperforming prescription steroids in head-to-head comparisons.

The most cited evidence is a 2014 randomized, blind, controlled trial published in Quintessence International that compared topical honey with topical triamcinolone acetonide 0.1% and with a commercial pain-relieving oral paste in adults with recurrent minor canker sores. The honey group reported complete pain relief within about one day on average, compared with roughly four days for the steroid and eight days for the paste. Ulcer size and erythema also fell faster in the honey group. A more recent 2025 randomized clinical trial in the European Journal of Oral Sciences testing thyme honey reported greater reductions in ulcer size and pain than triamcinolone at days 5 and 7.

The proposed mechanism is a combination of mild antimicrobial activity, an anti-inflammatory effect, and a simple physical barrier that protects the ulcer from the abrasion of eating and talking.

A note for shoppers: trial protocols generally used medical-grade honey or characterized varieties such as manuka or thyme. Standard supermarket honey may or may not have similar effects, since composition varies widely.

A small swap with real, if imperfect, evidence

Sodium lauryl sulfate, usually labeled SLS on the toothpaste tube, is the foaming detergent that gives most toothpastes their satisfying lather. For most people it does nothing more than make brushing feel familiar. For people who get canker sores often, there is reasonable evidence that switching to an SLS-free toothpaste may reduce how often and how severely those sores show up.

A 2019 systematic review in the Journal of Oral Pathology & Medicine pooled the available trials and concluded that, despite some conflicting individual studies, the body of evidence consistently leans toward fewer and less severe ulcers with SLS-free toothpaste. Mayo Clinic specifically recommends foaming-agent-free toothpastes such as Biotene or Sensodyne ProNamel for people prone to flares.

The honest framing matters here. This is a prevention strategy, not an emergency one. Switching toothpastes today is unlikely to shrink today's sore by tomorrow. But for a chronic sufferer, swapping in an SLS-free option for a few months is a low-cost experiment with reasonable upside.

The simplest tool for in-the-moment relief

Sometimes the best evidence-backed move is the most boring one. Letting a small ice chip dissolve slowly over a canker sore, or sipping cold water through the day, can quietly take the edge off in a way that is hard to beat for ease and cost. The mechanism is straightforward: cold reduces local inflammation and temporarily numbs the nerve endings around the ulcer.

Mayo Clinic and Harvard Health Publishing both list cold as a first-line self-care suggestion, particularly in the few minutes before a meal when the goal is to make eating tolerable. Dedicated randomized trials of ice for canker sores specifically do not really exist, which is unsurprising, because the physiology of cold-induced numbing and vasoconstriction is well established.

Practical detail: let the chip melt rather than chewing it, and avoid pressing it hard against the sore. Brief contact is enough.

Short bursts of numbing relief

Over-the-counter topical anesthetic gels and pastes containing benzocaine, usually around twenty percent, sit at the top of Mayo Clinic's treatment guidance for pain relief, with Cleveland Clinic offering a similar recommendation in its overview. Familiar drugstore names include Anbesol, Orabase, Kank-A, and Zilactin-B. A small amount applied directly to the sore tends to deliver somewhere between five and fifteen minutes of meaningful numbing.

The important caveat is that these products treat pain only. They do not shorten the life of the sore, kill bacteria, or seal the wound. They make the next half hour easier, which is sometimes exactly what is needed.

For more severe pain, a clinician may prescribe a lidocaine-based rinse or a compounded "magic mouthwash," which can offer longer and deeper numbing.

A clinically studied protective barrier

Hyaluronic acid, the same molecule used in many skincare serums, also shows up in oral gels designed for mouth ulcers. The idea is to apply a thin layer of gel directly to the sore two or three times a day, ideally after eating, where it acts as a protective barrier and a hydration aid for the surrounding tissue.

The supporting clinical evidence is more recent and more focused than most readers expect from a "natural" sounding option. A 2022 double-blind, placebo-controlled randomized trial published in BioMed Research International tested a 0.2% hyaluronic acid oral gel against placebo in adults with minor recurrent canker sores and found significant reductions in both ulcer size and pain scores in the hyaluronic acid group during the first week. An earlier evidence-based dentistry summary in Nature had previously noted that the benefits, while real, tend to be most pronounced for pain reduction in the early days of an ulcer.

Hyaluronic acid oral gels are increasingly available over the counter at pharmacies and online. Look for products designed specifically for oral use rather than skincare formulations.

A step up for stubborn or recurrent flares

Chlorhexidine gluconate is a broad-spectrum antiseptic mouthwash that dentists have used for decades, most often after gum surgery. Its role in canker sore care is supportive: by lowering the overall bacterial load in the mouth, it may reduce the secondary infection and inflammation that can keep a sore feeling worse than it needs to.

A double-blind, placebo-controlled cross-over trial of 0.2% chlorhexidine gluconate showed reductions in pain and severity of minor canker sores compared with placebo, although it did not clearly reduce the number of new ulcers. A later literature review in the Journal of Clinical and Experimental Dentistry came to a similar conclusion, while emphasizing that chlorhexidine works best as a short-term tool rather than a daily-forever rinse.

Typical use is a ten-milliliter rinse for about thirty seconds, two to four times a day, for up to two weeks. Longer continuous use can cause reversible tooth staining and altered taste, which is why dental teams usually pair it with a defined endpoint.

Availability varies by country. In some markets chlorhexidine mouthwash is over the counter; in others it is prescription-only. A pharmacist or dentist can confirm what is local.

The conventional first-line option for severe sores

For canker sores that are larger, slower to heal, or simply too painful to wait out, the long-standing prescription answer is a topical corticosteroid applied directly to the ulcer. The two most familiar agents are triamcinolone acetonide 0.1% paste and fluocinonide gel or ointment, usually applied two to four times a day until the sore heals.

The supporting evidence is among the strongest in the entire category. A 2025 systematic review and meta-analysis in BMC Oral Health pooled the available randomized trials and concluded that 0.1% triamcinolone consistently shortens healing time and reduces pain compared with placebo in minor recurrent canker sores. A 2022 network meta-analysis in Medicina (Kaunas) put triamcinolone in the top tier alongside honey, amlexanox, glycyrrhiza, and laser therapy.

This is a short-course tool, not a daily preventive. Most clinicians limit use to the active flare. People with a history of oral candidiasis, immune suppression, or pregnancy should flag those factors when discussing the option, since they may affect what gets prescribed.

A single, intense application for fast relief

For a sore that is unusually painful and not responding to gentler measures, chemical cautery is the speed lever. The two main options are Debacterol, a sulfonated phenolics and sulfuric acid solution available in single-use swabs in some markets, and silver nitrate, which is typically applied by a dentist or physician in-office. Both work by chemically destroying the surface nerve endings at the ulcer and sealing the tissue.

Mayo Clinic notes that Debacterol may shorten healing time to about a week for some sores, while silver nitrate has been shown to reduce pain without reliably accelerating healing. A randomized controlled trial of silver nitrate cautery confirmed that a single application significantly reduced pain severity versus placebo but did not significantly shorten healing. The Debacterol product label on DailyMed describes one application directly to the ulcer for rapid pain relief.

The trade-off is intensity. Cautery stings on contact, briefly but noticeably. Each sore is treated only once, and the option is generally reserved for minor canker sores in typical locations. Sores in unusual locations, sores larger than the standard "minor" category, or sores in anyone with an undiagnosed underlying condition are best evaluated before cautery is considered.

A non-invasive, in-office option with growing evidence

Low-level laser therapy, sometimes called photobiomodulation, is a non-invasive in-office treatment that uses a low-power diode laser, often at 660 or 808 nanometers, for a few seconds to a few minutes per sore. It is quiet, painless during application, and increasingly available at dental offices that have invested in the equipment.

The case for it has strengthened recently. A 2024 systematic review and meta-analysis in Systematic Reviews pooled fourteen trials covering 664 patients and concluded that low-level laser therapy consistently reduced pain scores in recurrent aphthous stomatitis compared with sham or conventional treatment. A subset of trials also reported shorter healing times. The mechanism is thought to involve stimulation of cellular repair, reduction of local inflammation, and modulation of pain signaling at the ulcer site.

The honest caveats are practical rather than clinical. Not every dental office offers it. Out-of-pocket cost varies and insurance coverage is inconsistent, especially in the United States. And the evidence base, while growing, is still mixed in terms of which laser type, wavelength, and protocol works best. A dental office that offers the treatment routinely can usually walk a patient through what to expect.

A prevention strategy with surprisingly robust trial evidence

For anyone who gets canker sores three or more times a year, a conversation with a doctor about vitamin B12 status is one of the most useful evidence-backed moves on this list, even though it is not what most search results would suggest.

The pivotal evidence is a 2009 randomized, double-blind, placebo-controlled trial published in the Journal of the American Board of Family Medicine in which adults with recurrent canker sores took either 1,000 micrograms of sublingual vitamin B12 daily or a placebo for six months. By months five and six, the treatment group showed significant reductions in the number of canker sore episodes, total days with ulcers, and pain scores. Notably, the effect held even in participants whose baseline B12 levels were within the normal range, which the PubMed citation of the same trial also flags as a clinically meaningful finding.

The proposed mechanism is that B12 deficiency, even subclinical, can affect normal cell turnover in the oral epithelium. Correcting it supports the rapid tissue regeneration that the mouth lining is constantly performing.

This is a prevention play, not an emergency one. Sublingual B12 will not heal a sore today. But for a person whose flares are a regular part of life, a quick blood test and a low-cost supplement may meaningfully reduce how often they happen.

The table below is not a ranking. It is a way to scan eleven options against three practical filters at once: how strong the supporting evidence is, what the option is primarily good for, and where someone would go to get it.

A few common moves can quietly make a canker sore worse. The most consistent advice across Mayo Clinic and other major centers is to avoid acidic foods and drinks (citrus, tomato, pineapple, vinegar dressings, coffee), spicy and salty foods that chemically irritate the sore, and hard or sharp foods like chips, pretzels, or crusty bread that can re-injure the area. Aggressive brushing and any picking or popping of the sore prolongs healing and raises the risk of secondary infection. Switching to a soft-bristled toothbrush during a flare is a small, helpful upgrade.

Alcohol-based mouthwashes are worth a special mention. "I'd also stay away from mouthwashes that contain alcohol," noted Dr. Nitin Kapur, a primary care physician at Cedars-Sinai. "We all like that minty taste, but alcohol-based mouthwash can cause a lot of irritation in the mouth."

This article is about canker sores, the small ulcers that show up on the soft tissue inside the mouth and are not contagious. Cold sores, by contrast, appear on the outside of the lips, are caused by herpes simplex virus type 1, and are contagious. The two are sometimes used interchangeably in everyday conversation, but the conditions, the treatments, and the precautions are different. The NCBI Bookshelf overview of mouth ulcers has a helpful side-by-side if it would be useful to dig deeper.

Most canker sores heal on their own within about two weeks. A handful of patterns deserve more attention. A sore that is larger than a centimeter, about the size of a pea, or that has not healed after two weeks, fits the pattern Mayo Clinic flags for clinical evaluation. So does a sore that prevents normal eating or drinking, a sore that comes with a fever, or a sore that extends to the outside of the lip.

Recurrence patterns matter too. Dr. Kapur put it this way at Cedars-Sinai: "Most people who get recurrent canker sores will get them two to three times a year, on and off, starting by the time they're 30 years old. But if you're older and you get a canker sore for the first time, that may be an indication something else is going on, so you'll want to seek medical advice."

Mouth ulcers can occasionally be a clue to an underlying condition such as celiac disease, inflammatory bowel disease, Behçet's disease, or a nutritional deficiency. Recurring fevers, eye inflammation, joint pain, persistent diarrhea, or unintentional weight loss alongside a canker sore are all worth mentioning to a clinician.

Canker sores are common, frustrating, and almost always self-limited. Within the next ten to fourteen days, the small white-rimmed crater inside the mouth will heal whether anything is done or not. What the evidence above offers is the difference between waiting it out and shaping the experience: less pain in the meantime, often a quicker timeline, and for chronic sufferers, real ways to reduce how often the next one shows up. The best plan is usually the simplest one that suits the situation, layered with a willingness to escalate to a dentist or doctor if the sore steps outside what is typical.

This article is for general informational purposes and is not a substitute for professional medical advice. Anyone with a mouth sore that is severe, recurrent, persistent, or accompanied by other unexplained symptoms is encouraged to speak with a licensed dentist, physician, or other qualified healthcare professional.