A variety of acne medications with proved efficacy are used in the United States. The selection of the prescription medication for the patient is based on the severity and type of acne. Patients with mild to severe acne can be treated with topical or oral medicines. Although systemic therapy is mainly used for treatment of severe acne, it is sometimes needed for moderate cases.
A variety of systemic agents used to clear acne include interlesional corticosteroid injection, isotretinoin, oral antibiotics (tetracycline and erythromycin) and oral contraceptives. Interlesional corticosteroid injection is a much – diluted corticosteroid injected by the dermatologist to treat severely inflamed cysts and prevent scarring. It helps treat acne by “melting” the cyst over a period of 3-5 days. Isotretinoin (a derivative of vitamin A) is a very effective oral drug that can help prevent scarring but because of its potential for serious side effects it is contraindicated in pregnant women and in many other conditions. Isotretinoin acts by reducing the size of the sebaceous glands thus preventing the excess secretion of oil and thereby decreasing the growth of bacteria. It has been estimated that up to 90% of patients’ treatment with isotretinoin result in complete or almost complete recovery from cystic acne.
Tetracycline and erythromycin are effective broad-spectrum oral antibiotics used to treat moderate to severe inflammatory acne. Tetracycline reduces inflammatory lesions of acne but is contraindicated in pregnant and breast feeding women, and children of less than 8 years of age. Doxycycline and minocycline, the synthetic derivatives of tetracycline, are also used to treat acne. Appropriate oral contraceptives that are valuable adjuncts in the treatment of acne in females include: ethynodiol, norgestimate, norethindrone and norethindrone acetate. They act by inhibiting the overactivity of sebaceous glands (oil glands).
Azelaic acid, benzoyl peroxide, clindamycin, erythromycin, and sodium sulfacetamide are the prescription topical antimicrobials used to treat acne vulgaris in the United States. Azelaic acid is a naturally occurring acid that has bacteriostatic and keratolytic properties. Benzoyl peroxide is inexpensive and best at killing P. acnes. When used in combination with antibiotics (erythromycin, clindamycin), benzoyl peroxide increases efficacy and reduces antibiotic resistance. Clindamycin is a safe and well tolerated semi-synthetic antibiotic that acts by reducing P. acnes and decreasing inflammation. Topical erythromycin is an antimicrobial and anti-inflammatory agent but may cause skin dryness and possible irritation. Sodium sulfacetamide products mostly contain sulfur and are used in patients who cannot tolerate other topical antimicrobials.
Several types of prescription topical retinoids used to treat acne include adapalene, tazarotene, and tretinoin. Adapalene is a synthetic retinoid analog that unclogs pores and demonstrates anti-inflammatory properties. Tazarotene is a second-line retinoid option that helps treat acne by stopping the development of new comedones. Tretinoin is a natural retinoid that works to gradually unclog pores and keep them unplugged.