Background: Atypical anorexia nervosa is an eating disorder that involves significant restriction of food intake leading to clinically significant weight loss despite remaining at a normal or above normal weight for age or height. Part of rehabilitation involves increasing calorie intake for nutritional rehabilitation and weight gain to an appropriate percentage of ideal body weight, determined based on patient weight history. This report highlights the importance of considering how increased food intake in a previously malnourished patient can affect the metabolism of medications they are taking for the management of co-occurring psychiatric conditions, including the possibility of the emergence or re-emergence of tardive dyskinesia for a patient on an antipsychotic.
Case presentation: This case presents a 43-year-old female with a history of bipolar disorder type 1, controlled on lurasidone, admitted to an inpatient eating disorder unit for nutritional rehabilitation and weight restoration for atypical anorexia nervosa. Shortly after admission, despite no initial change in medication dosing, the patient began exhibiting symptoms of tardive dyskinesia. These symptoms were reduced once her lurasidone dose was decreased.
Conclusions: Nutritional rehabilitation likely has an impact on the metabolism of certain antipsychotic medications including lurasidone. More research is needed involving patients recovering from a restrictive eating disorder who are on antipsychotic medications and the frequency of increased side effects, including tardive dyskinesia, with refeeding.
Keywords: Anorexia; Case report; Lurasidone; Nutritional rehabilitation; Tardive dyskinesia.
© 2025. The Author(s).