The article presents the results of evaluating the effectiveness of isotretinoin as the main drug therapy in patients with persistent and severe forms of seborrheic dermatitis.Materials and methods. 20 patients used systemic isotretinoin at a dose of 10 mg every second day for 12 weeks. The assessment of the quality of therapy was carried out by taking into account the dynamics of indicators at the 8th and 12th weeks. To assess the effectiveness of therapy evaluation scales of the dermatological index of the symptom scale and questionnaires of the dermatologists’ quality of life index DLQI (Dermatologists’ Quality of Life Index) were used.Results. According to the assessment of the scale of the dermatological index of symptoms, the greatest effectiveness of the drug was manifested in a decrease in skin erythema as a percentage from 76% at the 8th week of treatment to 91% at the 12th week of treatment from their initial manifestations. In addition, a pronounced effect was found in indicators of itching symptoms from 83% to 97% and desquamation from 79% to 95%, respectively. In addition, based on the DLQI questionnaire (Quality of Life Index in Dermatology), the data obtained demonstrated a distinct improvement in the quality of life of patients: both at the 8th week of treatment and after completion of therapy at the 12th week. From 79% at week 8 to 97% after treatment.Conclusions. The use of low doses of systemic isotretinoin proved to be an effective method of drug therapy for severe seborrheic dermatitis.