Canker sores (aphthous ulcers) are common lesions that form on the soft tissues inside the mouth, such as the inner cheeks, lips, and tongue. These small, non-contagious ulcers are typically white or yellowish with a distinct red border and can cause significant pain, making speaking and eating difficult. Salt water application is an accessible home remedy frequently used to manage discomfort and promote healing.
The Action of Salt on Mouth Sores
The effectiveness of salt on canker sores is based on biological principles that alter the wound environment. When applied, the salt solution exerts an osmotic effect, actively drawing excess fluid out of the damaged tissue surrounding the sore. This action helps reduce the swelling and inflammation that contribute to pain.
The application of salt water also creates a temporary, highly alkaline environment within the mouth. This higher pH level is less hospitable for oral bacteria, which tend to thrive in acidic conditions. By inhibiting bacterial growth, the salt rinse assists in keeping the ulcer clean, supporting the body’s natural healing process. Salt also possesses mild antimicrobial properties that reduce the presence of pathogens near the open wound.
Step-by-Step Application and Duration
To prepare the salt solution, a standard ratio involves dissolving approximately one teaspoon of table salt into a half-cup or full cup of warm water. The water should be warm, not hot, as excessive heat can irritate delicate oral tissues and worsen discomfort. Stir the mixture thoroughly until the salt granules have fully dissolved.
The most common and safest method is a gentle rinse: take a mouthful of the solution and swish it around your mouth. Focus on getting the liquid to saturate the canker sore area without aggressive or painful gargling. Hold the salt water in your mouth, swishing gently, before spitting it out completely.
The recommended duration for the rinse is brief, typically between 15 and 30 seconds, to maximize the therapeutic effect without causing irritation. Leaving the solution in the mouth for too long, or using a highly concentrated mixture, can be counterproductive, potentially causing a burning sensation or drying out the surrounding healthy tissue. While a small amount of salt paste can be dabbed directly onto the sore for targeted application, this method is highly irritating and is not generally recommended over the rinse.
Safe Frequency of Use and When to Seek Medical Advice
The salt water rinse can be safely repeated multiple times throughout the day, particularly after meals, to keep the sore clean and provide relief. A typical frequency is three to four times per day, or every few hours as needed, especially during the first few days. Spit the solution out after each rinse and avoid swallowing it to prevent excessive sodium intake.
Overusing the salt rinse, or making the solution too strong, can lead to dryness or irritation of the healthy mucous membranes, which may delay the healing process. If the canker sore does not show signs of improvement after seven days of consistent home treatment, or if the lesion is unusually large, professional guidance may be necessary.
Consult a doctor or dentist if the canker sore persists for two weeks or longer, or if you experience frequent, recurring outbreaks. Other warning signs include sores that extend onto the outer lip, extreme difficulty eating or drinking, or if the sore is accompanied by a high fever. These symptoms may indicate an underlying health issue or a more severe lesion requiring prescription treatments.