The fastest way to get rid of a mouth sore depends on what kind of sore you have, but several treatments can cut days off healing time and relieve pain within hours. Canker sores and cold sores are the two most common types, and they respond to entirely different treatments. A topical corticosteroid applied early can shrink a canker sore noticeably within a few days, while a high-dose antiviral taken at the first tingle of a cold sore can shorten the episode by about a day. Beyond those front-line options, a range of over-the-counter products, professional procedures, and even a few home remedies have real evidence behind them.
Canker Sores Versus Cold Sores
Before reaching for any remedy, figure out which kind of mouth sore you’re dealing with, because using the wrong treatment wastes time. Canker sores (aphthous ulcers) are shallow, round or oval sores that appear inside the mouth on the soft tissue of the cheeks, tongue, or gums. They are not contagious, and their cause is still not entirely understood. Cold sores (herpes labialis) are fluid-filled blisters that typically form on or near the lips, caused by herpes simplex virus. They are contagious and tend to recur in the same spot. If your sore is inside the mouth and has a whitish or yellowish center with a red border, it is almost certainly a canker sore. If it started as a cluster of tiny blisters on your lip or at the lip line, it is a cold sore. The treatments below are organized by sore type so you can skip to what applies to you.
Topical Corticosteroids for Canker Sores
If you want a canker sore gone as quickly as possible, a topical corticosteroid paste is the most widely studied prescription option. Triamcinolone acetonide 0.1% is the go-to formulation. You apply a small amount directly to the ulcer, typically four times a day, and it works by suppressing the local inflammatory response that keeps the sore painful and swollen. In a randomized trial comparing triamcinolone to laser therapy, both pain and ulcer size dropped significantly from day one to day three, with continued improvement through day ten.1PubMed Central. Comparative Evaluation of Low-Level Laser Therapy and Topical Triamcinolone Acetonide 0.1% in Recurrent Aphthous Stomatitis Subjects Another trial had patients apply the paste four times daily for six days and found meaningful reductions in ulcer parameters over that period.2Diyala Journal of Medicine. Comparative Evaluation of The Efficacy of Topical Hyaluronic Acid (0.2%) and Topical Triamcinolone Acetonide (0.1%) in The Treatment of Recurrent Aphthous Stomatitis
Triamcinolone is available by prescription in many countries and sometimes over the counter in others. It comes as both a cream and an ointment. The ointment version tends to adhere better to wet oral tissue, which is important because anything you put inside your mouth will be washed away by saliva relatively quickly. A practical tip: dry the sore gently with a tissue before applying the paste, and try not to eat or drink for at least 30 minutes afterward. Starting treatment within the first day or two of the sore appearing gives the best results.
Over-the-Counter Barrier Products
Not everyone has quick access to a prescription steroid, and most canker sores don’t strictly require one. Several over-the-counter products form a physical barrier over the ulcer, shielding it from food, drinks, and the friction of your tongue and teeth. That shielding alone can dramatically reduce pain.
Hyaluronic acid gels and rinses are among the best-studied barrier options. A retrospective study of patients using a hyaluronic acid barrier-forming mouth rinse or gel found significant reductions in pain, lesion color, and lesion size during the treatment course.3PubMed Central. Treatment of recurrent aphthous stomatitis (RAS; aphthae; canker sores) with a barrier forming mouth rinse or topical gel formulation containing hyaluronic acid: a retrospective clinical study A separate trial found that 0.2% hyaluronic acid applied topically cut soreness for up to four hours after each application and reduced the size of ulcerated areas after about four weeks of use.4PubMed. The efficacy of topical hyaluronic acid in the management of oral lichen planus One evidence review characterized the immediate pain relief from hyaluronic acid as primarily a protective barrier effect, shielding the raw nerve endings in the ulcer from stimuli in the mouth.5PubMed. Transient benefits for topical hyaluronic acid in recurrent aphthous ulceration
The advantage of hyaluronic acid products is that they’re available without a prescription, have virtually no side effects, and can be reapplied throughout the day whenever pain flares. They won’t necessarily make the ulcer heal faster in the way a steroid does, but they make the wait far more bearable. Look for oral-specific formulations rather than general hyaluronic acid serums, which aren’t designed to adhere in the mouth.
Adhesive hydrocolloid patches designed for canker sores work on the same barrier principle. You stick a small, flexible disc over the sore, and it stays put for several hours, protecting the area from mechanical irritation and letting medication (if the patch is medicated) absorb slowly. These patches have become increasingly popular as an over-the-counter option, and many users find the physical coverage alone reduces pain enough to eat and talk normally.
Silver Nitrate Cautery for Same-Day Pain Relief
If you need pain relief today rather than over the next few days, chemical cautery with silver nitrate is one of the most dramatic options. A dentist or doctor touches the canker sore briefly with a silver nitrate stick, which chemically burns the top layer of the ulcer. It stings intensely for a few seconds, and then the pain from the sore itself drops sharply. In a randomized controlled trial, about 70% of patients treated with silver nitrate reported reduced pain severity just one day after the procedure, compared to roughly 11% in the placebo group.6PubMed. Silver nitrate cautery in aphthous stomatitis: a randomized controlled trial
There’s an important nuance here, though. That same trial found that by day seven, healing rates were essentially the same in both groups, with around 83-89% of ulcers fully re-epithelialized regardless of treatment.6PubMed. Silver nitrate cautery in aphthous stomatitis: a randomized controlled trial So silver nitrate is a pain-relief intervention more than a healing-speed intervention. It won’t make the sore disappear any sooner than it would have on its own, but it can make the days between now and healing much more comfortable. If you have a canker sore that’s interfering with eating, speaking, or sleeping, this is worth asking your dentist about.
Antiseptic Mouth Rinses
Chlorhexidine gluconate rinses, typically at a 0.12% or 0.2% concentration, have been used for decades to manage oral ulcers. The idea is straightforward: keeping the bacterial load in the mouth low helps prevent secondary infection of the ulcer and may support faster healing. A 1% chlorhexidine rinse was tested head-to-head against a traditional herbal preparation in one trial and showed effectiveness in reducing pain and promoting healing of aphthous sores.7International Journal of Ayurvedic Medicine. A Randomised Control Trial comparing the efficacy of Jati Ghrita and 1% Chlorhexidine Gluconate on Aphthous Stomatitis
In practice, chlorhexidine is best used as a complement to other treatments rather than a standalone remedy. Swishing with it twice a day keeps the ulcer area clean and can reduce pain modestly, but it won’t shrink the sore as effectively as a steroid paste. One downside to be aware of: prolonged use of chlorhexidine can stain teeth and alter taste. For a single canker sore episode lasting a week or so, that’s usually not a concern. If you get canker sores frequently and want to use chlorhexidine regularly, talk to your dentist about balancing the benefits against the cosmetic side effects.
Cold Sore Antivirals
Cold sores call for a completely different approach because they’re caused by a virus, not by the immune or inflammatory mechanisms behind canker sores. The fastest treatment is a high-dose, short-duration course of the antiviral valacyclovir. Two large randomized, placebo-controlled studies found that taking 2 grams of valacyclovir twice in one day, started at the first sign of a cold sore, shortened the median episode duration by about a day compared to placebo. Pain and time to lesion healing were also reduced.8PubMed Central. High-dose, short-duration, early valacyclovir therapy for episodic treatment of cold sores: results of two randomized, placebo-controlled, multicenter studies
One day might not sound like much, but for something that typically lasts a week to ten days, it’s a meaningful difference, especially because antivirals also reduce the severity of symptoms during the episode. The key is timing. Antivirals work best when taken at the prodromal stage, the initial tingling or burning sensation that usually precedes visible blisters by several hours. If you get cold sores regularly, ask your doctor for a prescription you can keep on hand so you can start treatment the moment you feel that familiar warning sign. Waiting until blisters have already formed and crusted reduces the benefit substantially.
Over-the-counter options for cold sores include docosanol cream (sold as Abreva in the U.S.), which can modestly shorten healing time if used early and frequently. It’s less effective than prescription antivirals but doesn’t require a doctor visit.
Honey as a Home Remedy
Among the many home remedies people try for mouth sores, honey has the strongest evidence. It has natural antibacterial properties, forms a protective coating over the sore, and contains compounds that may support tissue repair. An animal study comparing different honey delivery systems found that honey gel applied to oral ulcers produced significantly better macroscopic healing by the third and seventh days compared to controls.9PubMed Central. Effect of two different delivery systems of honey on the healing of oral ulcer in an animal model Histological examination in that study showed the honey gel group had significantly better tissue repair over time.
If you want to try honey on a canker sore, dab a small amount of raw or medical-grade honey directly on the sore a few times a day, ideally after meals and before bed. Regular store-bought honey works in a pinch, but raw honey or Manuka honey tends to retain more of the bioactive compounds. The main downside is that it’s sticky and sweet, which can be unpleasant, and it won’t adhere to the sore as long as a medical gel would. But for something you already have in your kitchen, the evidence suggests it’s more than just folklore.
Other common home remedies include saltwater rinses, baking soda pastes, and ice. Saltwater rinses are mildly antiseptic and can temporarily reduce pain, and they’re unlikely to cause harm. Baking soda paste can neutralize acids that irritate the sore. Ice numbs the area briefly. None of these have the same level of clinical evidence as the treatments described above, but they’re reasonable comfort measures between applications of a more effective treatment.
Laser Therapy at the Dentist’s Office
Low-level laser therapy, sometimes called photobiomodulation, is an in-office treatment where a dental professional directs a low-power laser at the sore for a few minutes. The light energy is thought to stimulate cellular repair processes and reduce inflammation. Clinical reports have described excellent results in relieving pain and achieving complete remission of oral ulcers with this approach.10PubMed Central. Low laser therapy as an effective treatment of recurrent aphtous ulcers: a clinical case reporting two locations And as mentioned earlier, a randomized trial found that laser therapy performed comparably to triamcinolone paste in reducing pain and ulcer size over ten days.1PubMed Central. Comparative Evaluation of Low-Level Laser Therapy and Topical Triamcinolone Acetonide 0.1% in Recurrent Aphthous Stomatitis Subjects
The practical limitation is access. Not every dental office has a low-level laser device, and the treatment may not be covered by insurance. But if you get frequent, severe canker sores and live near a practice that offers this service, it’s worth asking about. Many patients report immediate pain relief after a single session, and the treatment itself is painless.
Preventing the Next Outbreak
Getting rid of a mouth sore fast is one thing. Keeping it from coming back is another. If you get canker sores more than a few times a year, a few evidence-based adjustments can reduce how often they appear.
Your toothpaste might be part of the problem. Sodium lauryl sulfate (SLS) is a foaming agent found in most commercial toothpastes, and a systematic review found that switching to an SLS-free toothpaste significantly reduced the number of ulcers, the duration of each ulcer, the number of recurrent episodes, and the level of pain in people prone to canker sores.11PubMed. Effect of sodium lauryl sulfate on recurrent aphthous stomatitis: A systematic review SLS-free toothpastes are widely available and cost about the same as regular options. This is one of the simplest changes you can make, and the evidence behind it is surprisingly consistent.
Nutritional gaps also play a role. A study comparing the dietary intake of people with recurrent canker sores to national reference data found that canker sore patients consumed significantly less vitamin B12 and folate than the general population, even though their intake of most other nutrients was equal or higher.12PubMed Central. Reduced dietary intake of vitamin B12 and folate in patients with recurrent aphthous stomatitis This doesn’t prove that low B12 or folate causes canker sores, but the association is strong enough that checking your levels with a simple blood test is reasonable if you get frequent outbreaks. Iron and zinc deficiencies have also been linked to recurrent mouth ulcers in other research. Correcting a genuine deficiency through diet or supplementation is straightforward and low-risk.
Stress is another contributor. A scoping review found a correlation between elevated salivary cortisol levels in people under psychological stress and an increased incidence of recurrent canker sores.13Indonesian Journal of Dentistry. Correlation between Salivary Cortisol Levels in Patients with Psychological Stress and Incidence of Recurrent Aphthous Stomatitis: A Scoping Review If you notice your canker sores tend to appear during exam periods, work deadlines, or other high-stress stretches, that pattern is probably not a coincidence. Managing stress won’t eliminate canker sores entirely, but it may reduce how often they appear.
When Mouth Sores Signal Something Else
Most mouth sores are standalone annoyances that heal on their own within one to two weeks. But recurring or unusually severe mouth ulcers can sometimes be a symptom of a systemic condition. Behçet’s disease, for example, is a chronic inflammatory condition that commonly affects the oral mucosa along with the eyes, skin, and joints. About 10-15% of Behçet’s patients also develop gastrointestinal involvement that can resemble Crohn’s disease.14PubMed Central. Similarities and differences between Behçet’s disease and Crohn’s disease Crohn’s disease itself can cause oral ulcers, as can celiac disease, inflammatory bowel disease more broadly, and certain immune deficiencies.
You should see a doctor or dentist if your mouth sores last longer than three weeks without healing, recur frequently and severely, are accompanied by fever or other systemic symptoms, or appear alongside unexplained weight loss, joint pain, eye inflammation, or persistent digestive problems. A single canker sore that heals in a week is normal. A pattern of large, deep ulcers that take weeks to resolve and come back every month deserves investigation. The treatments in this article are designed for ordinary canker sores and cold sores. If those remedies aren’t helping or your symptoms seem disproportionate, the sores may be a signal rather than the main problem.
Putting Together a Treatment Plan
The fastest approach combines pain relief with actual healing support, and the specifics depend on what you have access to. For a canker sore, the ideal combination is a topical corticosteroid applied directly to the sore starting as early as possible, supplemented with a hyaluronic acid gel or barrier product between steroid applications for ongoing pain relief, and a chlorhexidine or saltwater rinse to keep the area clean. If the sore is very painful and you can get to a dentist quickly, silver nitrate cautery or laser therapy can provide rapid relief that same day.
For a cold sore, the critical step is starting valacyclovir within hours of the first symptom. Between antiviral doses, keeping the area moisturized with a lip balm and avoiding picking at the blister helps prevent cracking and secondary infection. Over-the-counter docosanol cream can be applied alongside the antiviral.
For either type of sore, avoid acidic, spicy, or sharp-edged foods that will irritate the area. Eat on the opposite side of your mouth if possible. Stick to soft, cool foods during the worst of it. These aren’t treatments in themselves, but they stop you from undoing the work that your actual treatments are doing. And if you’re prone to recurrent canker sores, switching to an SLS-free toothpaste, addressing any nutritional gaps, and managing stress are the three longest-lever prevention strategies the research supports.