Inadequate nutritional rehabilitation of severely malnourished adolescents with Anorexia Nervosa (AN) increases the risk of medical complications. There is no consensus on best practices for inpatient nutritional rehabilitation and medical stabilization for severe AN. This study aimed to elaborate an admission protocol for adolescents with severe AN based on a comprehensive narrative review of current evidence. A Pubmed search was conducted in July 2017 and updated in August 2020, using the keywords severe AN or eating disorders (ED), management guidelines and adolescent. Relevant references cited in these guidelines were retrieved. A secondary search was conducted using AN or ED and refeeding protocol, refeeding syndrome (RS), hypophosphatemia, hypoglycemia, cardiac monitoring or cardiac complications. Evidence obtained was used to develop the admission protocol. Selective blood tests were proposed during the first three days of nutritional rehabilitation. Higher initial caloric intake is supported by evidence. Continuous nasogastric tube feeding was proposed for patients with a BMI < 12 kg/m2. We monitor hypoglycemia for 72 h. Continuous cardiac monitoring for bradycardia <30 BPM and systematic phosphate supplementation should be considered. Developing protocols is necessary to improve standardization of care. We provide an example of an inpatient admission protocol for adolescents with severe AN.