Treatment of Acna Vulgaris Part I

High rates of treatment failure often happens in women over 25 years old. Approximately 80% of women fail multiple courses of systemic antibiotic medications and approximately 30% to 40% fail after a course of isotretinoin (endocrinology disorder should be considered). 

Topical treatments for patients with acne include benzoyl peroxide (BP), salicylic acid (SA), antibiotic medications, combination antibiotic medications with BP, retinoid medications, retinoid with BP, retinoid with antibiotic medication, azelaic acid, and sulfone agents. Topical agents are safer than oral medications for pregnant or lactating women.

Benzoyl Peroxide

BP is available in a variety of strengths (2.5-10%) and formulations (cream, gel, wash, foam, aqueous gel, leave-on, and wash-off). BP is a comedolytic, keratolytic, anti-inflammatory agent with antimicrobial properties. BP is bactericidal mainly against P. acnes. The combination of BP and antibiotic therapy enhances results and may reduce antibiotic resistance development. Topical BP in varying formulations may be used 1 to 3 times daily as tolerated. Lower concentrations (2.5-5%), water-based, and wash-off agents may be better tolerated in patients with more sensitive skin.

Salicylic Acid

SA (0.5 to 2%) is a comedolytic agent in both wash-off and leave-on preparations. BP and SA are the most widely used over-the-counter topical acne treatments and are often used in combination. SA may be applied 1 to 3 times daily as tolerated. SA has an FDA pregnancy rating of C.

Topical Antibiotic 

Topical antibiotic alone is not recommended because high rates of resistent. It is best used in combination with BP. The main topical antibiotic medications are clindamycin and erythromycin.

1. Topical clindamycin 1% solution or gel is preferred and recommended dosing is an application of a thin layer once daily.

2. Topical erythromycin is less efficacious in patients with acne than clindamycin because of P. acnes resistance. It is usually administered 1 to 2 times daily.

3. Fixed-combination agents are available with erythromycin 3% plus BP 5%, clindamycin 1% plus BP 5%, and clindamycin 1% plus BP 3.75%. It is usually administered 1 to 2 times daily.

Topical Retinoid 

It's vitamin A–derivative prescription agents. It's often used as first-line treatment for  mild-to-moderate acne, especially comedonal. Retinoid therapy is comedolytic and resolves the precursor microcomedone lesion. Topical retinoid treatments are the mainstay in the maintenance of clearance after discontinuation of oral therapy. 

Tretinoin (0.025-0.1% in cream, gel, or microsphere gel vehicles), adapalene (0.1% cream, gel, or lotion and 0.3% gel), and tazarotene (0.05%, 0.1% cream, gel, or foam) are usually used. The recommended dosing is application of a thin layer once daily in the evening and avoid sensitive areas (e.g., eyelids, perioral area, nasal creases, and mucous membranes). Sunscreen lotion should be used to prevent photosensitivity.

Available combination agents that contain retinoid include adapalene 0.1% plus BP 2.5% and adapalene 0.3% plus BP 2.5% gels, which are approved for use in patients older than 9 years. In addition, clindamycin phosphate 1.2% plus tretinoin 0.025% gel is approved for patients older than 12 years of age. 

Tretinoin and adapalene are classified as FDA pregnancy category C but tazarotene is category X. Patients should be counseled on these pregnancy risks when initiating retinoid treatment if they desire pregnancy.

TO BE CONTINUED

Reference 

Tan, A. U. et al., 2018,'A review of diagnosis and treatment of acne in adult female patients', Int J Womens Dermatol, vol. 4, no. 2, pp. 56-71