Anorexia nervosa (AN) is often accompanied by various and serious physical complications. When treating AN patients with malnutrition, clinicians must address refeeding syndrome, which is occasionally life-threatening. Psychiatric ward staff, who have less experience with medical treatments, may have difficulty treating patients with AN. Accordingly, we have developed a comprehensive program to treat AN patients safely and efficiently in psychiatry units. The program provides both medical treatment and psychotherapy. After this program was introduced in our inpatient psychiatry unit four years ago, hypophosphatemia, which is often observed in patients with refeeding syndrome, has never occurred. In addition, the program's use resulted in less burden to the staff concerning the medical management of patients, thus providing increased time for the patients' mental care. Here we describe our program in detail, and we report the differences in patient outcomes before and after its introduction. Patients who have both mental illness and severe medical complications need to be treated simultaneously by physicians and psychiatrists, and AN patients in Japan are generally treated at a general hospital. There are few facilities and clinicians that can treat AN in Japan at this time, and the concentration of AN patients to a limited number of hospitals has resulted in a delay of treatment initiation and medical staff 's exhaustion. In 2015, a treatment and support center was initiated in Japan as part of an eating disorders project, toward the development of a treatment system for all patients with eating disorders. This treatment and support center is comprised of three institutions, and of these three, the Shizuoka center is designated as the psychiatry component. In Shizuoka Prefecture, three general hospitals and three psychiatric hospitals provide the treatment system for eating disorders to provide equal treatment quality for all patients in the catchment area. AN patients are assigned to the appropriate facility based on the severity of their malnutrition, i.e. weight and physical condition.
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