Dalacin is good for treating mild acne

Topical and systemic therapy

Acne can significantly disfigure a face and is therefore a psychological burden for most of the young people affected. There is no ideal acne therapy, but for most patients a suitable treatment strategy can be found that significantly reduces skin changes.

Acne is a chronic inflammatory disease of the sebum follicle, which is associated with seborrhea, non-inflammatory changes (open and closed comedones), inflammatory lesions (papules, pustules) and scarring of varying degrees (Fig. 2). Androgen-induced sebum production, altered keratinization, inflammatory processes and bacterial colonization of the hair follicles on the face, neck, chest and back with Propionibacterium acnes are involved in the pathogenesis of acne. Most 15 to 17 year olds have some degree of acne changes, 15 to 20% have moderate to severe acne. In our society, where flawless skin is almost a must, acne can severely affect the quality of life and lead to psychosomatic symptoms, depression, social withdrawal and suicidal ideation. These problems ameliorate with effective acne therapy.

There are numerous over-the-counter and prescription drugs available for acne treatment, so there is a wealth of combination options. However, comparative studies are rare, which is why many recommendations in international therapy guidelines are based on expert opinion. According to these guidelines, the choice of initial treatment should be based on the severity and appearance of the acne (predominantly inflammatory or non-inflammatory changes). Before starting treatment, the acne skin should be photographed in order to be able to assess later how the patient is responding to the treatment. In addition, the patient's mental health should be assessed.

Topical treatment options

Topicals are effective in monotherapy or combination therapy for mild acne with open and closed comedones and individual inflammatory lesions. The different treatment options have different mechanisms of action. Because topical preparations reduce the development of new acne changes, they must be applied to the entire affected area, not just individual lesions. Most topicals initially cause skin irritation. This can be countered by initially applying low-concentration preparations and gradually increasing the frequency of use or the dose. If the skin irritation persists, it is advisable to change the formulation and, for example, switch from an alcoholic solution to moisturizing creams or lotions.

Benzoyl peroxide

Benzoyl peroxide is a safe and effective substance. Benzoyl peroxide monotherapy works as well as oral antibiotics, and it works better than topical (iso) tretinoin for inflammatory lesions. Benzoyl peroxide initially causes local skin irritation, of which the patient must be informed.

In most cases, the skin irritation subsides - especially if the patient initially only applies the substance every other day and then increases the frequency. Low benzoyl peroxide concentrations (2.5 or 5%) are recommended as these are less irritating to the skin. In addition, there is no clear evidence that higher concentrations are more effective.

Topical retinoids

Retinoids such as tretinoin, adapalene, isotretinoin and tazarotene are contraindicated during pregnancy. So women of reproductive age must use contraception effectively when using retinoids. Topical retinoids have an anti-inflammatory effect on the abnormal keratinization and are therefore suitable for inflammatory and comedo acne. Future studies should compare retinoids with each other and with other acne therapeutics. Randomized controlled studies have shown that preparations with higher concentrations are more effective, but also lead to more pronounced skin irritation. All topical retinoids induce local reactions. If these are severe, the preparation must be discontinued. Retinoids can make the skin more sensitive to UV light.

Topical antibiotics

Topical antibiotics include clindamycin, erythromycin, and tetracycline. How topical antibiotics improve acne is not known in detail, but they appear to act directly on Propionibacterium acnes and reduce inflammation. Topical antibiotics are not as effective as other acne therapeutics for non-inflammatory lesions. For the treatment of more pronounced forms of acne, topical antibiotics are usually combined with other substances such as topical retinoids or benzoyl peroxide. Patients with acne lesions on their backs may respond better to oral antibiotics because it is difficult to apply topicals to large, hard-to-reach areas of skin. Alcohol-based preparations are more likely to dry out the skin and are therefore more suitable for oily skin. The effectiveness of erythromycin is likely to decrease due to increasing bacterial resistance.

Other topical substances

Salicylic acid has a keratolytic effect and is contained in many over-the-counter acne preparations. There are no studies that support the preferred use of salicylic acid compared to other topicals. The data on sulfur, resorcinol, zinc, aluminum chloride and sodium sulfacetamide are limited. Azelaic acid has antimicrobial and comedolytic properties, but can cause hypopigmentation.

Topical combinations

Combinations of different topicals with different mechanisms of action should work better than the individual substances. However, only a few combinations were correctly compared with the respective individual components; Patient compliance can be improved with acne therapeutics that are applied once a day, because they are easy to use and their effect occurs more quickly. However, it can be cheaper to prescribe generic monotherapeutic drugs and use them at the same time.

It is important to know that benzoyl peroxide inactivates tretinoin. If both substances are to be used, one should be applied in the evening and the other in the morning.

Oral antibiotics

Oral antibiotics are mainly used for more severe forms of acne, for acne predominantly localized on the trunk, for acne that does not respond to topical drugs, and for patients at increased risk of scarring. Antibiotics reduce the number of inflammatory lesions, but they cannot make them go away completely. There is no convincing evidence that any particular antibiotic is superior to another (including first and second generation tetracyclines) or that oral antibiotics are more effective than topicals for mild to moderate acne. There is also no evidence that higher doses are more effective than lower doses or that sustained-release preparations are necessary.

The choice of antibiotic should therefore be based on the patient's wishes, the side effect profile and the costs. Tetracyclines (tetracycline, doxycycline) are among the preferred options. Minocycline has significant side effects. Co-trimoxazole should be avoided because the sulfamethoxazole component has significant side effects. Quinolones are not recommended for adolescents due to the risk of arthropathy, and oral ciprofloxacin shows rapid selectivity, which promotes resistance. Aminoglycosides and chloramphenicol are only effective to a very limited extent. Oral clindamycin, while effective, can cause serious side effects such as pseudomembranous colitis. There is increasing resistance to macrolides (erythromycin and azithromycin) and trimethoprim.

The use of antibiotics for acne therapy has been questioned because of resistance problems, especially because antibiotics in this indication were administered over long periods of time and in low doses. Simultaneous use of benzoyl peroxide can reduce the problems of bacterial resistance, while simultaneous use of oral and topical antibiotics should be avoided. The success of acne therapy with antibiotics should be assessed after six to eight weeks. If a patient no longer responds to antibiotics, it is not helpful to increase the frequency or dose. Antibiotics should not be routinely used as maintenance therapy because there are similarly effective alternatives.

Oral contraceptives

Combined oral contraceptives (COC) contain an estrogen (ethinylestradiol) and a progesterone. Many women with acne are prescribed COC because estrogen inhibits the activity of the sebum and reduces the formation of androgens. Contraceptives that contain only progesterone often worsen acne.
Hormone therapy should be used early in women with moderate to severe acne, as well as in women with seborrhea, hirsutism, or alopecia. Preparations containing cyproterone acetate have traditionally been used to treat acne, but there is little evidence that cyproterone acetate is superior to other progestins. This also applies to the anti-androgenic effects of spironolactone.

Oral isotretinoin

When oral tretinoin is administered over a period of about 20 weeks, it is the most effective medication and results in clinical cure in about 85% of cases. The recurrence rate is around 21% and is dose-dependent. The best results are achieved with daily doses of 1 mg / kg or with a maximum dose of 150 mg / kg over the entire duration of treatment.

Isotretinoin is mostly reserved for severe acne cases with lumps and cysts and a tendency to scarring, and for patients who do not respond to other therapies. Isotretinoin leads to cheilitis, dry skin, nosebleeds, secondary infections, temporary deterioration of lesions, photosensitivity and an increase in serum lipids. But these side effects are rarely so severe that treatment must be stopped.

Because of the teratogenicity of isotretinoin, adequate contraception must be used when treating women of childbearing potential with isotretinoin.

Andrea W├╝lker

Approved and edited reprint from Ars medici 7/2012

The authors declare that there are no conflicts of interest.

Williams HC et al .: Acne vulgaris. The Lancet 2012; 379: 361-372.