Acne conglobata and acne fulminans are severe forms of acne requiring a special approach to both diagnosis and treatment. The combination of genetic predisposition, features of the innate and adaptive immune responses, presence of comorbid pathologies in patient, skin reaction to stress are currently considered to be the pathogenetic mechanisms, which form the basis of developing severe forms of acne. The main factors provoking the development of severe forms of acne have been described, the correlation between acne conglobata, acne fulminans and metabolic syndrome has been demonstrated, the main diagnostic criteria of severe forms of acne and characteristics of therapeutic tactics in these forms of the disease have been formulated, the algorithmic approach of managing patients with acne fulminans has been provided. Alternative methods of managing patients with acne fulminans resistant to performed therapy have been presented. Acne conglobate and acne fulminans require timely and accurate diagnosis, as well as personalized approach to treatment. A differentiated approach, preciseness and patient’s adherence to therapy effectively help to prevent the complications of severe forms of acne and to minimize the post-acne manifestations, primarily in the form of severe cicatricial changes.