Treatment approach

Because multiple factors influence acne development, combination therapy is the mainstay of treatment, except in mild-to-moderate comedonal acne. It is generally agreed that topical retinoids should be considered for inclusion in combination treatments of most patients; they can also prevent and improve hyperpigmentation associated with inflammatory acne lesions, particularly in patients with darker skin.

Mild-to-moderate acne

Comedonal acne is especially responsive to topical retinoids. In mild, primarily comedonal acne, topical retinoids are the treatment of choice and are used as monotherapy. [32] [C Evidence]

Salicylic acid has been used for years for its keratolytic properties, but few well-designed trials of its safety and efficacy are available. [33] It is considered a less effective comedolytic agent than topical retinoids.

For inflammatory acne, combination therapy is the mainstay of treatment. [34] These products may be used individually in combination, or together as a combination product (erythromycin/benzoyl peroxide, clindamycin/benzoyl peroxide). [35] Topical retinoids (tretinoin,[C Evidence] adapalene, [36] [B Evidence] and tazarotene) are prescribed in combination with benzoyl peroxide[C Evidence] and/or topical antibiotics (clindamycin,[C Evidence] erythromycin,[C Evidence]or dapsone). [37] Topical antibiotics may be combined with benzoyl peroxide, thus potentially increasing patient compliance and decreasing the risk of antibiotic resistance development.

Adapalene-benzoyl peroxide is a novel combination treatment combining 2 known effective drugs for treatment of comedonal and noncomedonal acne. [38] [39] [40]

Azelaic acid is an antimicrobial with mild comedolytic and anti-inflammatory properties, which can be used adjunctively in inflammatory acne. [41] It can be helpful in reducing post-inflammatory hyperpigmentation.

Moderate-to-severe acne

Moderate-to-severe comedonal acne with minimal inflammation may respond to topical retinoids alone.[C Evidence][B Evidence][C Evidence] Moderate-to-severe inflammatory acne is best treated by a combination of an oral antibiotic[C Evidence] and a topical retinoid. These drugs should not be used alone, due to potential for developing antibiotic resistance. [42] If oral antibiotics are used for more than 2 months without significant improvement, then the addition of benzoyl peroxide to the treatment regimen should be considered to reduce the chance of resistance and to increase efficacy of the antibacterial treatment. [32]

Oral antibiotics are typically administered for at least 6 to 8 weeks and up to several months, although some patients require indefinite antibiotic therapy. If repeat treatment is necessary, an antibiotic that was effective in the past is prescribed again; otherwise, an alternative antibiotic can be prescribed. If 2 antibiotics from different classes are ineffective, a culture could be performed to help guide antibiotic selection. It is generally agreed that topical and oral antibiotics should not be used as monotherapy. [32]

Azelaic acid is an antimicrobial with mild comedolytic and anti-inflammatory properties, which can be used adjunctively in inflammatory acne. [41] It can be helpful in reducing post-inflammatory hyperpigmentation.

Severe nodulocystic acne or resistant to standard treatment

For severe acne or acne unresponsive to other treatments, a course of oral isotretinoin for 5 to 6 months is the treatment of choice. Patients often report that more standard acne treatments work better after a course of isotretinoin, but some patients may require a repeat course of isotretinoin. Adverse effects with this drug can be severe, and regular monitoring during treatment is required. [32] Severe headaches, decreased night vision, or signs of adverse psychiatric events are signs for prompt discontinuation. Isotretinoin is teratogenic; therefore, women need to undergo pregnancy tests before starting isotretinoin, and monthly while taking the drug.

Oral corticosteroids such as prednisolone may be considered as adjunctive treatment to calm the skin down before initiating isotretinoin, or in conjunction with isotretinoin for patients with severe acne flare or acne fulminans (a type of severe nodulocystic acne). In these instances, oral corticosteroids are generally used for 1 to 4 months to avoid relapse. [3]

Acne in females with hormonal involvement

Hormonal therapy may be used in women who experience acne flares associated with menstrual periods. It can also be helpful in patients with proven ovarian or adrenal hyperandrogenism and in patients with polycystic ovary syndrome. Treatment options include combined oral contraceptives containing cyproterone plus ethinyloestradiol, or anti-androgenic drugs including spironolactone. [43] Treatment may require specialist endocrinologist involvement. [44]

Acne in pregnant women

In pregnant women with severe acne, only a few topicals are considered category B and safe to use in pregnancy, including clindamycin, erythromycin, and azelaic acid.