As with other drugs, azelaic acid has side effects which must be taken into account. The side effects of azelaic acid therapy depend on the duration of the therapy, the dosage and the frequency of use. They are very different from one individual to another.
In general, creams and ointments containing azelaic acid are well tolerated so that side effects usually occur at the beginning of the therapy and are only temporary. Most frequent are local skin symptoms like redness of the skin, skin dryness and water retention. In addition, there may be a slight burning, itching or irritation of the skin at the applied skin areas.
Slight pain is also possible. A little less frequently, nervous sensations, skin peeling and discoloration of the skin occur. Azelaic acid interacts with the melanocytes of the skin in a dose-dependent manner, so that the skin becomes slightly lighter when used over a longer period of time.
Rare side effects of azelaic acid therapy are contact dermatitis. Contact dermatitis is an allergic reaction of the skin to a certain substance with which it comes into contact. Other rare side effects are generalised allergic reactions and drug hypersensitivity.
These can manifest themselves for example in an asthmatic attack. In rare cases, eczema, ulcers, blisters and overheating may occur at the site of application. All these side effects, however, depend on the dosage of azelaic acid and the area of application, as well as the individual who uses the active ingredient.
Azelaic acid should not come into contact with mucous membranes or the eyes as it causes irritation. In case of contact, the affected mucous membranes should be rinsed immediately. If irritation persists, a dermatologist must be consulted.
During pregnancy, azelaic acid should only be used after consultation with a dermatologist and with strict indication. The same applies to breastfeeding. In this case, however, the child must under no circumstances come into contact with the active substance. In case of complaints, the dermatologist should be consulted in order to be able to assess whether it is only a slight and temporary intolerance or, for example, a drug allergy.
Azelaic acid in the treatment of acne
Azelaic acid has been used for the topical treatment of acne for about 20 years. There are no major contraindications to treat acne with azelaic acid. For a better understanding of the therapy it is recommended to know a few facts about the development and symptoms of acne.
Acne is a collective term for diseases of the sebaceous glands and hair follicles of the skin, which initially lead to the formation of blackheads, so-called comedones. Later, other skin symptoms such as papules, pustules, redness and nodules develop. This is the most common skin disease worldwide.
There are a number of different factors that lead to the development of acne. Some of them, such as a genetic predisposition or smoking, cannot be influenced by therapy with azelaic acid. However, other mechanisms of development are influenced by the mechanisms of action of azelaic acid, so that a relief of the symptoms results.
There are three important main mechanisms of action of azelaic acid which intervene in the pathogenesis of acne. Azelaic acid has an anticomedogenic effect. This means that it reduces the development of blackheads and prevents them in the disease-free interval.
This is achieved by the fact that azelaic acid on the one hand inhibits the activity of the keratinocytes of the skin and on the other hand reduces the number of free fatty acids of the skin. In acne, the activity of the keratinocytes is increased, resulting in the development of blackheads and clogged skin pores. The fatty acids are also increased in acne and represent an inflammatory stimulus for the skin.
Another important mode of action of azelaic acid is its antimicrobial effect. It has an inhibiting effect on the propionibacterium acnes. This bacterium plays a decisive role in the disease, especially in a later stage of acne.
Azelaic acid has an inhibitory effect on the bacterium. The anti-inflammatory effect also dampens the activity and the irritation of the bacterium on the skin. This can be called a para-antibiotic effect as it is not only directed directly against the bacterium but much more against the inflammation caused by the bacterial infestation.
The last important mechanism of action is the anti-inflammatory effect of azelaic acid. This results, among other things, from the inhibition of free fatty acids and helps to soothe the skin and alleviate the symptoms. Creams and ointments containing azelaic acid are recommended for moderate to severe acne in combination with other agents such as antibiotics, retinoids and hormonal antiandrogens.
A therapy with azelaic acid alone is not sufficient for moderate to severe acne as the expected success of the therapy would be too weak. In case of mild acne, the use of azelaic acid can be recommended. It should be noted that azelaic acid does not influence the hyperseborrhoea, i.e. the excessive sebum production of the skin in the course of acne.
A therapy with azelaic acid should be carried out for at least 12 weeks. The cream or ointment must be applied twice a day. Side effects, such as local skin reactions in the sense of redness, irritation, itching and the like, are usually only temporary and subside in most patients within 4 weeks.
Allergic reactions occur very rarely. There are no contraindications for the use of azelaic acid, as it is generally very well tolerated by patients with acne. Only contact with mucous membranes and the eyes should be avoided, as irritation can occur there.