Treatments used for acne

Acne therapies target different parts of the pathogenic process.

Over-the-counter products (eg benzoyl peroxide, salicylic acid, azelaic acidHoffman, 2017Sieber, 2014, niacinamide) are used to treat acne. Benzoyl peroxide is antibacterial, and can bleach coloured fabric (eg clothes, towels, pillowcases, sheets). Salicylic acid is a keratolytic, and unblocks pores by removing keratin plugs.

Retinoids, including topical retinoids (eg adapalene, tretinoin, trifarotene) and oral retinoids (eg isotretinoin), are used in acne.

Topical retinoids promote removal of keratin plugs, prevent reblocking of pores and suppress inflammation. Introduce topical retinoids gradually because they can irritate the skin initially. Apply every second night (after washing with a low-irritant, pH-balanced, soap-free cleanser) for the first 2 weeks, then apply every night. Apply the product to the whole area affected by acne, not just to single lesions. Remove the product by washing the face in the morning because topical retinoids can increase the skin’s sensitivity to sunlight. Choose a cream formulation for patients with dry or sensitive skin, and a gel formulation for those with oily skin.

Oral retinoids reduce incidence of blocked pores, markedly reduce sebum, indirectly reduce cutibacteria (formerly propionibacteria), and reduce inflammation.

Retinoids are teratogenic. Avoid topical and oral retinoids in patients who are planning to become pregnant, or who are pregnant. Avoid oral retinoids in patients who are breastfeeding. Topical retinoids may be used in patients who are breastfeeding (no data is available, but it is unlikely to be a concern because systemic absorption through the skin is minimal).

When treating acne, antibiotics, including topical antibiotics (eg clindamycin) and oral antibiotics (eg tetracyclines, erythromycin) are used for their anti-inflammatory action rather than their antibacterial effect.

Avoid using antibiotics long term. Once papular inflammation has resolved or inflammatory acne activity is controlled, stop the topical or oral antibiotic, and continue with a nonantibiotic topical preparation (eg topical retinoid, benzoyl peroxide) for maintenanceAsai, 2016The Australasian College of Dermatologists, 2021Zaenglein, 2016Zouboulis, 2015. Topical or oral antibiotics can be resumed if inflammation recurs, but review the ongoing need regularly.

Antiandrogens, such as the combined oral contraceptive pill (COCP) (containing a progestogen that is antiandrogenic or less androgenic than levonorgestrel) and spironolactone, can be used to treat acne in female patients; see Antiandrogen treatments for moderate to severe acne for discussion. Antiandrogens work by reducing androgen-mediated sebum production.

Although physical therapies (eg laser therapy, blue and fluorescent light therapy, microneedling, dermabrasion, chemical peels, sebaceous gland ablation) are commonly used, evidence supporting their use in active acne is lacking. The use of physical therapies can also delay effective treatment that could prevent scarring. The risk of complications is significant from some types of physical therapies. Physical therapies may provide transient improvement in acne, but maintenance treatments are usually required. Safe use of these therapies requires skilled practitioners (eg dermatologists, practitioners trained by and working under guidance of dermatologists).

Established scars are difficult to treat, and do not respond to topical or oral treatments for acne. Early referral to a dermatologist is recommended for postacne scarring.

Treatment choice will depend on acne severity; see treatments for mild and moderate to severe acne.