A variety of prescription medications are used today to clear acne. Topical (applied to the skin) medications may be prescribed for mild to severe acne. Systemic (works internally) therapy is needed to treat severe acne and may be used for moderate cases. These medications, which play an important role in acne treatment, attack the different factors that lead to acne. To achieve long-term control and resolution, dermatologists may combine therapies. The following describes the prescription medications used in the United States to treat acne:
Interlesional Corticosteroid Injection
When an acne cyst becomes severely inflamed, there is a good chance that it will rupture and scarring may result. To treat these severely inflamed cysts and prevent scarring, dermatologists may inject such cysts with a much-diluted corticosteroid. This lessens the inflammation and promotes healing. An interlesional corticosteroid injection works by "melting" the cyst over a period of 3 to 5 days.
Isotretinoin
Isotretinoin is a potent oral retinoid that is reserved for treatment of very severe cystic acne and severe acne that has proven itself resistant to other medications. For more information about isotretinoin, see Treating Severe Acne.
Oral Antibiotics
For patients with moderate to severe and persistent acne, oral antibiotics have been a mainstay of therapy for years. Like topical antimicrobials, oral antibiotics work to reduce the P. acnes population (a contributing factor in acne), which, in turn, decreases inflammation. Treatment with oral antibiotics usually begins with a higher dosage, which is reduced as acne resolves. Generally, antibiotics are prescribed for six months or less.
Over time, the P. acnes bacteria can become resistant to the antibiotic being used to treat it. When resistance occurs, acne is no longer controlled. Another antibiotic or alternative treatment can be prescribed. Numerous studies support the effectiveness of the following oral broad-spectrum antibiotics, which are used to treat acne in the United States:
- Erythromycin. It is effective against a broad spectrum of bacteria, including P. acnes. The most common side effect is irritation of the gastrointestinal tract.
- Tetracycline and derivatives. Tetracyclines reduce the papules and pustules (inflammatory lesions) of acne. These medications should not be taken by children younger than 8 years of age because they can affect growth and stain teeth. They should also not be taken by a woman who is pregnant or breast feeding. During pregnancy and breastfeeding, tetracyclines can affect the development of the child’s bones and teeth, leading to skeletal defects.
A typical tetracycline regimen for treating moderate to severe acne starts with a dose of 500 to 1000 milligrams a day, which is decreased as improvement occurs. Long-term, low-dose tetracycline therapy may be continued for many months to suppress acne. Higher doses may be prescribed for very severe acne.
Two synthetic derivatives of tetracycline used to treat acne are doxycycline and minocycline. Doxycycline proves especially effective in treating inflammatory acne. It can cause sun sensitivity in some patients. Minocyline has a long history of use in treating acne. It is often effective in treating acne that has not responded to other oral antibiotics. Minocycline also seems to produce fewer incidents of antibiotic resistance.
Oral Contraceptives
Oral contraceptives have been shown to effectively clear acne in women by suppressing the overactive sebaceous glands and can be used as long-term acne therapy. However, oral contraceptives should not be prescribed to women who smoke, have a blood-clotting disorder, are older than 35 or have a history of migraine headaches—without the advice of a gynecologist.
Topical Antimicrobials
Topical antimicrobials work to inhibit the P. acnes populations and are used to treat patients with mild to moderately severe inflammatory acne. They may be used alone or combined with a medication that works on another factor that leads to acne aside from P. acnes. A dermatologist can determine whether a topical antimicrobial is appropriate for a patient and if so which topical antimicrobial should be prescribed. Prescription topical antimicrobials used to treat acne vulgaris in the United States include:
- Azelaic acid. Naturally occurring in the skin, azelaic acid is used to treat mild to moderate inflammatory and non-inflammatory acne. It is believed that azelaic acid clears acne by reducing the populations of P. acnes, decreasing the abnormal shedding of skin cells and reducing inflammation. This medication has also proven effective in treating the dark spots that develop in some acne patients with skin of color. Azaleic acid is well tolerated by most people and can be safely used for years. Side effects may include skin dryness and lightening of the skin where applied.
- Benzoyl peroxide. Benzoyl peroxide works by killing P. acnes. However, it does not have anti-inflammatory abilities. It is available in a wide range of strengths and can be found as a gel, lotion, cleanser, cream and wash. Many acne preparations include benzoyl peroxide because research shows that benzoyl peroxide increases the effectiveness of some medicines, such as erythromycin and clindamycin. When used in combination with antibiotics, benzoyl peroxide also reduces the likelihood of a patient developing resistance to the antibiotic. The most common side effects are skin irritation, the potential to bleach hair and fabrics as well as possible allergic reaction.
- Clindamycin. A semi-synthetic antibiotic, topical clindamycin has a long history of successfully treating acne. It works by reducing P. acnes and decreasing inflammation. In topical form, clindamycin has proven safe and is well tolerated. Skin dryness and irritation are possible side effects. It is important to use as directed to decrease bacterial resistance that can occur with antibiotic use.
- Erythromycin. This topical antibiotic is active against a broad spectrum of bacteria, including P. acnes. Topical erythromycin, which is an antimicrobial and anti-inflammatory, is used primarily to treat acne. When topical erthyromycin is combined with benzoyl peroxide, the combination proves to be quite effective as the patient gets the effects of two antimicrobial agents. Like topical clindamycin, erythromycin may cause skin dryness and possible irritation. It is important to use as directed to decrease bacterial resistance that can occur with antibiotic use.
- Sodium sulfacetamide. A topical antibiotic that inhibits P. acnes and opens clogged pores, sodium sulfacetamide is effective in treating inflammatory acne. Many products containing sodium sulfacetamide include sulfur. Some patients do not like the smell of the sulfur or its grittiness. Usually, the newer products that contain sulfur do not have these problems.
Topical Retinoids
Prescribed to treat acne ranging from mild to moderately severe, topical retinoids are a derivative of vitamin A and considered a cornerstone in acne treatment. Retinoids work to unclog pores and prevent whiteheads and blackheads from forming. Topical retinoids can irritate the skin and increase sun sensitivity so it is important to use sun protection and follow the dermatologist’s directions to maximize effectiveness. An added benefit in using topical retinoids is that they may help diminish the signs of aging, such as fine lines and wrinkles. Topical retinoids currently prescribed for acne treatment in the United States include:
- Adapalene. A synthetic retinoid applied as a gel or cream, adapalene unclogs pores and possesses moderate to potent anti-inflammatory abilities. Improvement is usually seen in 8 to 12 weeks. Side effects include minor skin irritation and dryness.
- Tazarotene. A synthetic retinoid available as a gel or cream, it works to keep the skin’s pores clear and has proven effective in treating acne. This medication should not be used by women who are pregnant, and effective contraception is needed while taking tazarotene because the medication has produced birth defects in animals. Skin irritation is a possible side effect.
- Tretinoin. The first retinoid developed for topical use, tretinoin is a natural retinoid. It works to gradually unclog pores and keep them unplugged. In the past, many patients found tretinoin too harsh for their skin; however, the newer forms are proving less irritating. Side effects include redness, scaling, dryness, itching and burning. If these occur, talk with the dermatologist who prescribed tretinoin as these side effects can be managed by adjusting the amount applied and when it is applied.
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