How azelaic acid can be used to treat acne

Azelaic acid is a naturally occurring decarboxylic acid that was initially used back in the 1970s as a treatment for hyperpigmentation of skin. Incidentally it was also found to reduce acne, which as been confirmed by subsequent studies. Limited studies show that it works as well as oral tetracycline without any of its side effects. It is now considered an antimicrobial and it is recommended for treating mild to moderate acne, that is, both comedonal and inflammatory acne, mostly as a second line of treatment.

Mechanism of action

The mechanism by which it acts is not known as yet, but it has been antibacterial and anti-keratinizing properties. Thus it keeps skin pores clear by reducing the production of keratin whose accumulation could cause acne by blocking hair follicles. Azelaic acid works well on acne caused by bacteria but has no effect on acne that is not infected by bacteria.

Advantages

1) It does not cause bacterial resistance
2) Unlike benzoyl peroxide, it does not bleach or stain normal skin or clothing.
3) It is not photosensitive and so particularly useful in summer time and patients who cannot tolerate topical retinoids.
4) Helps reduce pigmentation, so it is particularly useful for dark skinned patients whose acne leaves persistent brown marks.
5) Treatment can be continued safely for months or years if the acne remains active.
6) Azelaic acid is non-toxic and fairly well tolerated with only 5% of patients having any complaints about side effects.

Disadvantages

1) Patients with dark skin should be monitored for hypopigmentation (too little skin color).
2) Patients with dark skin should be monitored for hypopigmentation (too little skin color). Those with sensitive skin or who suffer from eczema may especially find azelaic acid irritating to apply since a mild irritant dermatitis may result.
3) It should be used with caution in lactating or pregnant women.
4) The response of acne to azelaic acid treatment is slow. Normally improvement is seen after one month of treatment. Continuing application of the cream shows further improvement with maximum results usually obtained after six months of continuous treatment.

Dosing

Azelaic acid is applied topically as a 20% cream and a gel preparation. It is applied to affected areas after cleansing the skin once daily. If well tolerated the application is increased to twice daily. In case of patients with sensitive skin, to begin with, azelaic acid may be applied once in two days and then the frequency gradually increased to give time to the skin to adjust. Contact with eyes should be avoided.

Side effects

To date there have been no reports of serious side effects of the drug. When side effects do occur they are typically one or more of skin irritation, burning, stinging and erythema.