Nutritional replenishment for anorexia nervosa

Nutritional replenishment in a patient with anorexia nervosa aims to restore body weight to an appropriate body mass index (BMI) (see Classification of weight according to body mass index). Nutritional replenishment is used in inpatient or outpatient settings, depending on the severity of symptoms and other patient factors (see Principles of managing anorexia nervosa).

Involve a dietician experienced in the treatment of eating disorders during nutritional replenishment because there is risk of refeeding syndrome in patients with anorexia nervosa. Refeeding syndrome is a serious and potentially fatal complication of aggressive refeeding of a patient who has been malnourished for a long period of time—it can result in rapid onset of hypokalaemia, hypomagnesaemia and hypophosphataemia. However, underfeeding a severely malnourished patient in order to reduce the risk of refeeding syndrome, can also have negative consequences. To minimise the risk of refeeding syndrome and complications due to underfeeding, tailor nutritional replenishment to the patient’s needs. Monitor phosphate, potassium and magnesium, and administer electrolyte replacement if required—for management of electrolyte disturbances, see Hypokalaemia, Hypomagnesaemia and Hypophosphataemia. For further information on risks and management of refeeding syndrome, see here.