Acne treatments

Exfoliation is a common component of acne treatment programs. It is rarely effective on its own, but may be modestly useful in conjunction with other treatments. Since exfoliation removes dead, hardened outer skin cells, it improves the penetration of subsequently applied topical treatments. Whether exfoliation helps clear dead cells from deep inside the pores is debatable, but if it does, that would be helpful too. Common exfoliating agents used in acne include alpha-hydroxy acids (AHA) and beta-hydroxy acids (BHA). Overall, BHA, particularly salicylic acid, appears to be more useful because they also reduce sebum production.

Topical Antibacterials

Since bacterial growth (particularly of P. acnes) in pores is a factor in the developments of acne, topical bactericidal agents have been used as a treatment. The most common such agent is benzoyl peroxide, which is a strong oxidizer that kills bacteria by generating oxygen free radicals. The strong suite of benzoyl peroxide is that bacteria do not develop resistance to oxygen. Hence, if benzoyl peroxide works for you, it is likely to continue working as long as you use it. The downside is that free radicals are damaging not only to bacteria but to your skin as well: they cause irritation, dryness, cell damage and accelerate the rate of skin aging. Unfortunately, for many people, benzoyl peroxide is only effective topical treatment. In that case, it is prudent to find the lowest possible effective concentration. Concentrations of benzoyl peroxide as low as 2.5% may be effective, especially if combined with other treatments.

Other topical antibacterials that have been used for acne include triclosan, chlorhexidine gluconate, colloidal silver and tea tree oil. None of these appear to be as effective as benzoyl peroxide though.

Topical antibiotics

Topical antibiotics have an important advantage over benzoyl peroxide in that they kill acne-causing bacteria in a more targeted way, causing minimal collateral damage to the skin. Antibiotics most commonly used for topical acne treatment include erythromycin, clindamycin and tetracycline. Topical antibiotics are about as effective as oral ones but with far fewer side effects. However, if acne is present over large areas of the body, oral antibiotics may be easier to use. Antibiotic treatment for acne may not be sustainable over the long term because bacterial resistance may develop to any and all of these drugs.

Oral antibiotics

Oral antibiotics used to treat acne include erythromycin, tetracycline or their analogs (oxytetracycline, doxycycline, minocycline or lymecycline). Oral antibiotic appear to be about as effective as topical antibiotics but produce a variety of side effects, such as diarrhea, dysbacteriosis, colitis and others. The advantage of oral antibiotics over topicals is the ease of use, especially when acne affects large areas of the body. Also, occasional cases unresponsive to topical antibiotics (particularly those with deep cystic acne) would respond to oral administration. Antibiotic treatment for acne may not be sustainable over the long term because bacterial resistance may develop to any and all of these drugs.

Hormonal treatments

Androgens are a major factor in acne and reducing the levels and/or blocking/counterbalancing their action would generally improve acne. However, such treatments are inappropriate in men due to sexual and other side effects. In women, some estrogen/progestin contraceptive combinations were shown to reduce acne. Antiandrogens, such as cyproterone, alone or in combination with estrogens are even more effective. However, antiandrogens may sometimes affect sex drive and produce other side effect even in females. There is some evidence that topical antiandrogens (such as 5% topical spironolactone) may be modestly effective in acne.

Topical retinoids

Retinoids are active metabolites of vitamin A and their analogs. They improve acne by reducing sebum production an altering the lifecycle of epithelial skin cells (keratinocytes). Retinoids commonly used for acne include tretinoin (Retin-A), adapalene (Differin) and tazarotene (Tazorac).

Treatment with topical retinoids often causes temporary increase in acne outbreaks during the first several weeks of treatment. Retinoids may also cause skin irritation, dryness and flaking. Also, retinoids cause sensitivity to UV light and should not be used without a thorough sun protection.

Oral retinoids

Oral retinoids, such as isotretinoin (Accutane), are among the most effective acne treatments. They work by reducing production of sebum, altering the lifecycle of epithelial skin cells and possibly modifying other acne-causing factors as well. Isotretinoin has been shown to be highly effective in severe acne and can either improve or clear over 80% of patients. A course of treatment usually takes 4-6 month and, just like topical retinoids, may cause an initial flareup. As opposed to virtually all other acne treatments, isotretinoin often leads to long-term remission of acne. In those who relapse, recurrences tend to be milder.

Despite high effectiveness and durability of improvements, oral retinoids are infrequently used and are the treatment of last resort. Common side effects include dry skin and nosebleeds (due to dry mucosa). Less frequent side effects include liver damage, permanent skin texture changes, and elevated blood triglycerides. The drugs have been linked to cased of depression and psychosis. Oral retinoids should never be used in women who are or may become pregnant due to the high risk of birth defects.

Phototherapy

Some forms of visible light, in particular intense blue light, have been shown to reduce the number of acne lesions by 50 percent or more. It appears to work by interacting with porphyrins, a class of chemicals produces by acne-causing bacteria P. acnes. This interaction results in the production of noxious free radicals that are toxic to bacteria. The side effects of such treatment, if any, are generally mild because porphyrins and not present in skin cells and so the damage they produce is limited mainly to the bacteria. It appears that a combination of red and blue light is even more effective than the blue light alone. Good results are obtained with at least 2 treatments a week while daily treatments seem to be the most effective. Anywhere from one to three months of treatments are generally required to achieve substantial improvement. When treatment is discontinued, the improvement lasts longer than after benzoyl peroxide or antibiotics (up to several month). The main down side is the need for repeated office visits for treatments or, for home use, considerable cost of the equipment.

Photodynamic therapy

Another variation of the light-based therapy being explored is combining intense blue light with a photosensitizing agent, such as delta-aminolevulinic acid (ALA), which incrases the production of porphyrins. The results of this approach have been mixed. More research is needed to determine its role as an acne treatment.

Other treatments

A number of other treatments supported by limited scientific evidence are currently in use on a relatively small scale. More research is needed to confirm and better define their role in treating acne.

Topical azelaic acid: Azelaic acid (Azelex, Finevin, Skinoren) reduces sebum production possibly by partly blocking the effects of androgens. It inhibits the formation of comedones and may help in mild comedonal acne.

Topical tea tree oil: The oil of tea tree (Melaleuca) has both antibacterial and anti-inflammaory effects and in small studies was shown to be as effective as topical antibiotics

Topical Niacinamide: In a few small studies, 4% niacinamide gel was shown to be equally or more effective than topical antibiotics. Niacinamide is a form of (Vitamin B3). The effects are said to be due to the anti-inflammatory action of topical niacinamide.

Topical Retinaldehyde: Retinaldehyde, a form of vitamin A, is converted to retinoic acid (tretinoin) in the skin when applied topically. It also has been shown to have some antimicrobial activity against acne-causing bacteria. Such a combination appears to make retinaldehyde a viable dual-action acne treatment. However, further studies are needed to determine the scope of its effectiveness.

Heat therapy: Directed targeted heat (Zeno device) delivered to the area where an acne lesion is just beginning to form appears to make lesions milder and shorter-lived. The method does not seem to work on cystic acne.

Oral Vitamin B5: Oral Vitamin B5 (Pantothenic Acid) taken orally in large doses as calcium pantothenate has been claimed to improve acne. This has not been rigorously studied, however.