Amlexanox is a medicinal compound with anti-inflammatory and anti-allergic effects. It is formulated primarily as a 5% topical oral paste for direct application to affected tissues within the mouth. The substance is classified as an immunomodulator, a category of drugs that adjusts the immune response.
Mechanism of Action
The therapeutic effects of amlexanox stem from its ability to intervene in the body’s inflammatory processes at a cellular level. It functions as an inhibitor of specific enzymes known as TANK-binding kinase 1 (TBK1) and IKK-epsilon. By blocking these enzymes, amlexanox prevents certain immune cells, particularly mast cells and neutrophils, from releasing inflammatory mediators. These mediators include histamine and leukotrienes, which are substances the body produces that lead to inflammation, swelling, and pain.
This inhibition of mediator release is the core of its action. When applied to tissues, amlexanox helps to quiet the local immune response that causes the symptoms of certain inflammatory conditions. The drug also has antiallergic properties, which are demonstrated by its capacity to suppress both immediate and delayed hypersensitivity reactions in animal studies, though the direct relevance to its effect on oral ulcers is not fully established.
Approved Medical Applications
The primary medical use for amlexanox is for the treatment of recurrent aphthous ulcers, more commonly known as canker sores. These are small, painful lesions that develop on the soft tissues inside the mouth or at the base of the gums. Amlexanox is not a cure for canker sores but is a treatment that manages the symptoms and healing process.
When applied directly to a canker sore, amlexanox paste, often sold under the brand name Aphthasol, works to accelerate healing and reduce the associated pain. Clinical studies have shown that the 5% oral paste leads to faster resolution of the ulcers compared to no treatment or a placebo vehicle. The mucoadhesive nature of the paste allows it to stick to the moist surface of the ulcer, ensuring the drug remains in contact with the lesion to exert its effects.
Proper Administration and Dosage
For effective treatment of canker sores, amlexanox oral paste should be applied as soon as symptoms of an ulcer appear. The recommended application frequency is four times per day. It is best to apply the paste after oral hygiene routines following breakfast, lunch, dinner, and just before bedtime to maximize its contact time with the ulcer.
To apply, a small dab of the paste, about one-quarter of an inch (0.5 cm), should be squeezed onto a clean fingertip. The paste should then be gently dabbed onto each ulcer, ensuring the entire lesion is covered. It is important not to rub the paste in, as this can cause further irritation. After application, it is advised to avoid eating or drinking for at least 30 minutes. Treatment should continue until the ulcer is fully healed.
Potential Side Effects and Safety
The use of amlexanox is generally well-tolerated, but some individuals may experience side effects. The most common adverse reactions are localized to the application site and are typically mild and temporary. These can include a stinging, burning sensation, or pain immediately following application.
Less frequently, affecting under 1% of patients in clinical trials, side effects such as nausea, diarrhea, or contact mucositis have been reported. Although rare, it is possible to have a more serious allergic reaction to amlexanox. Signs of an allergic reaction include hives, rash, itching, or swelling of the face, lips, tongue, or throat, which may be accompanied by difficulty breathing. If any of these serious symptoms occur, use of the medication should be stopped immediately and medical attention should be sought.
Investigational and Off-Label Uses
Beyond its approved use for canker sores, amlexanox has been the subject of scientific research for other medical conditions, largely due to its anti-inflammatory properties. In Japan, it has been used as a treatment for bronchial asthma and allergic rhinitis. The drug’s ability to modulate immune responses has prompted studies into its potential for treating systemic diseases.
Researchers are exploring amlexanox as a potential therapy for metabolic disorders, including type 2 diabetes, obesity, and nonalcoholic fatty liver disease (NAFLD). Animal models have suggested that by targeting these pathways, amlexanox could help improve metabolic function. It is important to understand that these uses are currently investigational and amlexanox is not approved for treating these diseases.