Most mouth ulcers heal on their own within one to two weeks, but the right combination of home care and over-the-counter treatments can shave days off that timeline and dramatically cut pain in the meantime. The key is reducing inflammation early, keeping the ulcer clean, and avoiding the irritants that slow tissue repair.
Saltwater and Baking Soda Rinses
The simplest thing you can do right now is rinse with a mild alkaline saline solution. Mix 1 teaspoon of table salt and 1 teaspoon of baking soda into 4 cups of warm water. Swish gently for 30 seconds, spit, and repeat several times a day, especially after meals. The salt draws fluid from swollen tissue to reduce inflammation, while the baking soda neutralizes acids in your mouth that irritate the open sore. This won’t sting the way straight salt on a wound does, because the solution is dilute enough to be gentle on raw tissue.
Switch to SLS-Free Toothpaste
One of the fastest wins is checking the ingredient list on your toothpaste. Sodium lauryl sulfate (SLS) is a foaming agent in most commercial toothpastes, and it’s a known irritant for people prone to mouth ulcers. In a clinical study, patients who switched to an SLS-free toothpaste saw roughly a 70% reduction in ulcer occurrence compared to their baseline, and a 60% reduction compared to periods when they used a toothpaste containing SLS. If you’re dealing with a current ulcer, the switch removes a source of chemical irritation that’s actively slowing your healing. Look for toothpaste brands marketed as “gentle” or “sensitive” and confirm SLS isn’t on the label.
Over-the-Counter Pain Relief Options
OTC gels and pastes serve two purposes: numbing the pain so you can eat and drink, and in some cases, speeding up the healing itself. Not all products are equal here.
Benzocaine gels (like Orajel) are effective at numbing the sore quickly, but comparative research shows they produce slower overall recovery. Lidocaine gels offer short-term pain relief with moderate effects on inflammation and healing. If your main goal is faster healing rather than just pain control, look for a product containing amlexanox paste, which has been shown to significantly accelerate healing and reduce ulcer size within about a week. Choline salicylate gel is another option that provides rapid pain relief while also addressing inflammation.
For any topical product, dry the ulcer surface gently with a tissue before applying. This helps the medication stick rather than wash away with saliva.
Topical Corticosteroid Treatments
Corticosteroid pastes and rinses are the most effective treatment category for mouth ulcers, according to clinical guidelines. They work by suppressing the inflammatory response that causes pain and delays tissue repair. The most commonly used option is a prescription paste that you apply directly to the dried ulcer two to four times daily until it heals. For ulcers in hard-to-reach spots, a corticosteroid mouth rinse (swished and spit every 12 hours) can coat the area more effectively.
These are prescription products, so you’ll need to ask your doctor or dentist. They’re worth requesting if you get ulcers frequently or if your current one is particularly large or painful. They won’t prevent future ulcers from forming, but they reliably shorten the duration of active ones.
Honey as a Topical Treatment
Applying honey directly to a mouth ulcer is one of the better-supported natural remedies. In a study of pediatric cancer patients with oral mucositis (a condition that produces ulcers similar to canker sores), children treated with manuka honey experienced healing within about 3 days and reported significantly less pain than untreated groups. Honey creates a protective barrier over the sore, has natural antibacterial properties, and appears to actively promote tissue repair.
Dab a small amount of raw honey, ideally manuka honey, onto the ulcer a few times a day. It will taste better than most medicated gels, and it’s safe to swallow. Let it sit as long as possible before eating or drinking.
Chemical Cautery for Stubborn Ulcers
If you have a particularly painful ulcer that isn’t responding to other treatments, your dentist or doctor can chemically cauterize it. A product called Debacterol seals the ulcer surface in a single application and can reduce healing time to about a week. Silver nitrate, another cautery option, doesn’t speed healing but does provide pain relief. Both work by destroying the damaged nerve endings on the ulcer surface and sealing it off from further irritation. This is a quick in-office procedure, not something you do at home.
Vitamin B12 for Recurring Ulcers
If you get mouth ulcers repeatedly, a daily vitamin B12 supplement may break the cycle. A randomized, double-blind trial published in the Journal of the American Board of Family Medicine found that taking 1,000 micrograms of sublingual B12 daily for six months significantly reduced ulcer recurrence, regardless of whether participants had a measurable B12 deficiency at the start. The tablets dissolve under the tongue before bed. This won’t heal your current ulcer overnight, but if you’re someone who gets a new one every few weeks, it’s one of the few interventions shown to reduce how often they come back.
Iron and folate deficiencies are also linked to recurrent ulcers. If you get them frequently, it’s worth having your levels checked.
What to Avoid While Healing
Certain foods and habits actively slow ulcer healing. Acidic foods like citrus, tomatoes, and vinegar-based dressings irritate the exposed tissue. Spicy foods, crunchy chips, and hard bread can physically reopen the wound. Alcohol-based mouthwashes (most mainstream brands) dry out and sting the ulcer. Switch to a chlorhexidine rinse instead, which reduces pain and severity without the burn.
If you’re stressed or sleep-deprived, that matters too. Mouth ulcers are closely tied to immune function, and your body repairs tissue fastest when it’s well-rested. This isn’t a vague wellness suggestion. Stress is one of the most consistently reported triggers for recurrent ulcers.
When a Mouth Ulcer Needs Medical Attention
Any mouth sore that lasts longer than 10 days should be examined by a dentist or doctor to rule out something more serious, including precancerous changes. You should also seek evaluation if your ulcer is accompanied by fever, blisters on your skin, eye inflammation, or if you have a weakened immune system. Persistent sores without an obvious cause may require a biopsy. Most mouth ulcers are harmless and self-limiting, but the 10-day mark is the clear threshold for getting it checked.