Amlex5%

Amlex (as a 5% oromucosal paste) is an FDA-approved, evidence-based topical treatment with the following indications:

Established/FDA-approved use

• Recurrent aphthous ulcers (canker sores): Amlex oral paste is indicated for the treatment of aphthous ulcers (canker sores) of the mouth in patients with a normal immune system, to reduce ulcer pain and speed healing when applied at the first sign of an ulcer.

Historical/regional off-label use

• In some countries, an oral tablet form of Amlex has historically been used as an adjunct anti-allergic/anti-inflammatory agent for bronchial asthma and allergic conditions such as allergic rhinitis; this tablet formulation is not the standard, FDA-approved use and is not widely available or established in most markets, including Bangladesh, where the topical oral paste is the marketed form.

Amlex paste is not intended for ulcers caused by other conditions (e.g., herpes, trauma, systemic disease); a physician should evaluate ulcers that are unusually large, persistent, or recurrent.

Each gram of Amlexanox oral paste contains Amlexanox 50 mg (5% w/w) in an adhering oromucosal paste base.

In markets where an oral tablet form of Amlexanox exists, tablets typically contain Amlexanox 25 mg or 50 mg per tablet; this formulation is not the standard marketed form in Bangladesh.

Amlex is a synthetic anti-inflammatory and anti-allergic agent chemically classed as an aminoxanthone (anthranilic acid derivative). It is most widely used and marketed as a 5% topical oromucosal (oral) paste for the treatment of aphthous ulcers (canker sores).

Unlike systemic corticosteroids or antibiotics, Amlex acts locally at the site of application with limited systemic absorption when used as directed. It is not an antibiotic and has no antimicrobial action; it works by modulating local inflammatory and immune mediator release at the ulcer site.

Topical anti-inflammatory / anti-allergic agent for oral mucosal ulcers (oromucosal paste)

Mechanism of Action

Amlexanox inhibits the release of pre-formed inflammatory and allergic mediators, including histamine and leukotrienes (e.g., LTC4), from mast cells and other inflammatory cells at the site of the ulcer. It also inhibits the production of certain pro-inflammatory cytokines (such as IL-4 and TNF-alpha) at the local tissue level.

The exact mechanism by which this translates into faster healing and pain reduction of aphthous ulcers is not completely established, but its local anti-inflammatory and mast-cell-stabilizing action is believed to reduce local tissue inflammation, thereby reducing pain and promoting faster ulcer resolution.

Pharmacokinetics

When applied topically to the oral mucosa as directed, systemic absorption of Amlexanox is minimal. Any small amount absorbed is metabolized in the liver and excreted mainly via the kidneys.

For topical (oromucosal) use only. Not for ophthalmic, injectable, or oral (swallowed) use unless a physician has specifically prescribed a tablet form.

• Wash and dry hands before use.
• Gently dry the ulcer area with a clean tissue or cotton swab before application.
• Using a clean fingertip or cotton swab, apply a small (about 1/4-inch) dab of Amlex paste directly onto the ulcer; do not rub in.
• Apply after oral hygiene, 4 times a day (e.g., after breakfast, lunch, dinner, and at bedtime).
• Wash hands after application.
• Avoid eating or drinking immediately after application if possible, to allow the paste to adhere.

Because Amlex oral paste is applied topically and has minimal systemic absorption, clinically significant drug-drug interactions are not well established or expected.

• No formal interaction studies have identified clinically significant interactions between topical Amlex and other oral or systemic medications when used as directed.
• Avoid concurrent use of other topical oral products at the exact same application site at the same time, as this may reduce adhesion/effectiveness of the paste; space out applications of other oral topical products if both are needed.

Local application-site reactions are the most common side effects of Amlex and are generally mild and transient.

Common (approximately 1-2% of patients)

• Transient stinging, burning, or discomfort at the application site upon applying Amlex

Uncommon (less than 1%)

• Local irritation or contact mucositis
• Nausea
• Diarrhea

Rare

• Hypersensitivity reactions (rash, swelling); discontinue Amlex immediately and seek medical attention if these occur (see Contraindications).

Recurrent, unusually severe, or persistent mouth ulcers that do not respond to Amlex within 10 days should be evaluated by a physician or dentist to exclude other underlying causes.

Pregnancy: Human data on the use of Amlex in pregnancy are limited. Animal reproduction studies with Amlex have not shown adverse fetal effects at doses substantially higher than the human topical exposure, but adequate, well-controlled studies in pregnant women are lacking. Amlex should be used during pregnancy only if clearly needed, and only after consulting a physician who can weigh the potential benefit against any potential risk.

Lactation: It is not known whether topically applied Amlex passes into human breast milk in clinically relevant amounts. Because many drugs are excreted in human milk, caution is advised, and a physician should be consulted before using Amlex while breastfeeding.

• For external/topical oral use only. Amlex paste should not be swallowed in large amounts, injected, or applied to the eyes.
• Amlex is intended for common aphthous ulcers only; it is not a substitute for medical evaluation of mouth ulcers that are unusually large, numerous, persistent beyond 10 days, or associated with fever or other systemic symptoms, which may indicate another underlying cause.
• Local burning or stinging on application is common, generally mild, and transient; if severe irritation, worsening of the ulcer, or signs of an allergic reaction occur, discontinue Amlex and consult a physician (see Contraindications and Side Effects).
• Patients with a weakened immune system (e.g., due to HIV/AIDS, chemotherapy, or immunosuppressive therapy) should consult a physician before using Amlex, as safety and efficacy have not been specifically established in this population.
• Keep away from eyes; if accidental eye contact occurs, rinse thoroughly with water.

Topical overdose with Amlex paste is unlikely given the small quantities used per application and minimal systemic absorption. Applying excessive amounts may increase the likelihood of local irritation, stinging, or mucosal reaction at the application site but is not expected to cause systemic toxicity.

If Amlex paste is accidentally swallowed in a large quantity, or if any signs of a serious reaction occur, seek immediate medical attention or contact a poison control center/emergency services rather than attempting home treatment.

Store at room temperature (below 30°C), away from light and moisture. Keep the tube tightly closed and out of the reach of children.

Pediatric Use

The safety and efficacy of Amlex oral paste have not been established in children under 6 years of age. Use in this age group should only occur under medical supervision.

Elderly

No specific dose adjustment is required for elderly patients using topical Amlex; clinical experience has not identified age-specific safety concerns distinct from the general adult population.

Renal/Hepatic Impairment

Formal studies of Amlex in patients with renal or hepatic impairment have not been conducted; given minimal systemic absorption with topical use, specific dose adjustment is not established as necessary.

Immunocompromised Patients

Amlex has been studied primarily in patients with a normal immune system; patients who are immunocompromised should consult a physician before use (see Precautions and Warnings).

Apply Amlex paste starting at the first sign of an aphthous ulcer and continue 4 times daily until the ulcer has healed. If there is no improvement or healing within 10 days of starting Amlex, discontinue use and consult a physician or dentist to rule out other causes.

Topical anti-inflammatory/anti-allergic agent (aminoxanthone/anthranilic acid derivative); oromucosal preparation

Amlexanox works locally by inhibiting the release of histamine and leukotrienes from mast cells and other inflammatory cells, and by suppressing local production of certain pro-inflammatory cytokines, at the site of the aphthous ulcer. This local anti-inflammatory and mast-cell-stabilizing action is believed to reduce pain and promote faster healing of the ulcer.

B

The safety and efficacy of Amlex oral paste have not been established in children under 6 years of age. In older children and adolescents in whom aphthous ulcers occur, use of Amlex should be under the guidance of a physician or dentist, following the same application instructions as for adults (a 1/4-inch strip applied to each ulcer 4 times daily). Parents/caregivers should supervise application to avoid swallowing of the paste.