Aphthous lesions start with a lymphocyte followed by a neutrophil infiltrate and leukcytoclastic vasculitis. Therefore, topical steroids are of proven beneficial effect.(15). Literature suggests preparations such as a betamethasone sodium phosphate rinse (dissolving 0.5 mg in 5 mL of water and rinsing for 2–3 min) (3)

Betamethasone (formulated in a spray aerosol)  (3,15, 16,17,18,19) has anti-inflammatory, anti-pruritic, and vasoconstrictive actions and can be used in RAU.

Betamethasone spray aerosol evidence

No proprietary products indicated for RAS (Recurrent Aphthous Stomatitis) are currently available in Australia.

The following betamethasone dipropionate topical preparations are available overseas (United States and/or Canada) in aerosols strengths  of 0.1% and 0.05%. However, these preparations are contraindicated for internal use. 

• Alphatrex

• Diprolene AF

• Diprosone (Schering) Maxivate (Westwood-Squibb)   

• Occlucort (CAN)

• Rhoprosone (CAN)

• Taro-Sone (CAN) Teladar

Betamethasone Dipropionate Topical Aerosol  e.g. Diprosone; Diprolene 0.1% (unavailable in Australia)(17)

Contains: 6.4 mg betamethasone dipropionate, equivalent to 5.0 mg betamethasone, in a vehicle of mineral oil and caprylic/capric triglyceride; also containing 10% isopropyl alcohol and sufficient inert hydrocarbon (propane and isobutane) propellant to make 85 grams.

The aerosol spray deposits betamethasone dipropionate equivalent to approximately 0.1% betamethasone, in a non-volatile, almost invisible film. A 3 second spray delivers betamethasone dipropionate equivalent to approximately 0.06 mg betamethasone.(17) 

Mechanism of Action of treatment 

Betamethasone dipropionate is a synthetic glucocorticoid that is used topically on the skin. (The naturally-occurring glucocorticoids are cortisol and hydrocortisone which are produced by the adrenal gland). Glucocorticoids have potent anti-inflammatory activity while also suppressing the immune response. (16)

Betamethasone works via a similar mechanism to other corticosteroids. Please refer to  Topical corticosteroids and Potent Corticosteroids

Efficacy for RAS/RAU/mouth ulcers(17,18)

Indications for topical preparations include inflammatory and pruritic manifestations of moderate to severe EXTERNAL corticosteroid-responsive dermatoses. Betamethasone dipropionate spray aerosol is not indicated for RAU/RAS/mouth ulcers.

Precautions, limitations, contra-indications, disease contra-indications/drug interactions

Dose: Shake well and apply sparingly to the affected skin area 3 times a day. The container may be held upright or inverted during use. The spray should be directed onto the affected area from a distance of not more than 6 inches and applied for only 3 seconds. For the most effective and economical use, a 3 second spray is sufficient to cover an area about the size of the hand.

Adverse effects of dermatologic ointments, creams, sprays: Local burning, irritation, acneiform lesions, striae, skin atrophy, secondary infection.

Precautions:

• FOR EXTERNAL USE ONLY

• Examine area for infections, skin integrity before application

• Administer cautiously to pregnant patients; topical corticosteroids have caused teratogenic effects and can be systemically absorbed

• Apply sparingly

• Avoid contact with the eyes

• Irritation or infection at the site of application should be reported

• PREGNANCY Category: C

Contraindications

• Internal use (eye, mouth, nose)

The following tests may be helpful in evaluating HPA axis suppression due to excessive or prolonged use:

• Urinary free cortisol test

• ACTH stimulation test