Azelaic acid works by inhibiting the growth and reproduction of bacteria and has antibacterial properties. It also turns the keratinization process in the funnel part of the hair follicle to normal and inhibits acne formation. Side effects include itching, rash, and tingling sensation. Azelaic acid has antibacterial activity against Propionibacterium acnes and Staphylococcus epidermidis, which may be based on the principle of inhibiting the protein synthesis of microorganisms, and also regulates the keratinization process of the funneling part of the hair follicle, so azelaic acid has a very good therapeutic effect in the topical treatment of mild and moderate inflammatory acne vulgaris. Common side effects of azelaic acid include itching, erythema, rash, dermatitis, and flaking. Rarely, it can cause worsening of asthma, decreased skin pigmentation, leukoplakia, hirsutism, redness, and worsening of recurrent herpes labialis. It is contraindicated in people who are allergic to the product, used with caution in lactating women, and in pregnant women only when clearly needed. Therefore, it is necessary to strictly follow the doctor’s instructions for the use of medication.