Anorexia Nervosa (AN) is the psychiatric illness with the highest mortality, especially if it is associated with psychiatric and somatic comorbidity. Medical complications can be multiple and jeopardize the normal development of children and adolescents, even permanently. Although its prevalence is lower compared with other psychiatric disorders, its tendency to chronicity and the severity of its consequences are remarkable. Although outpatient treatment of anorexia is privileged as far as possible, the risks associated with poor response to treatment or lack of adherence of the patient or family, require the possibility of hospitalization at any time of the disease. We searched and analyzed the national and international literature available (especially clinical guidelines) about the indication for hospital treatment in AN and the interventions recognized as necessary and effective during hospitalization. Despite the lack of standardized criteria for hospitalization, the available information converge on the need for a multidisciplinary work by a specialist team, to make family interventions especially in adolescents and tailor treatment according to the individual physical, psychological and social needs.