Differential weight restoration on olanzapine versus fluoxetine in identical twins with anorexia nervosa

Abstract

Objective No studies have compared the response to selective serotonin reuptake inhibitors and atypical antipsychotics in anorexia nervosa. This case study examines such a comparison. Method This report describes a case of 12-year-old identical twins with anorexia nervosa, one of whom was treated with olanzapine and the other with fluoxetine, while undergoing family therapy. Results Twin A treated with fluoxetine went from 75% to 84.4% ideal body weight, while Twin B treated with olanzapine went from 72% to 99.9% ideal body weight over the course of 9 months. Discussion This case supports the need for adequately powered, controlled clinical trials to test the efficacy of olanzapine in adolescents presenting with anorexia nervosa.

Canadian practice guidelines for the treatment of children and adolescents with eating disorders

“…Seven case series (223 patients) also showed improvement in weight following treatment with FBT [26][27][28][29][30][31][32]. Eleven additional case reports (number of total patients = 29) are described showing benefit of FBT in terms of weight gain [33,[35][36][37][38][40][41][42][43][44]. Some of these focus on twins [35,42,44], comorbid conversion disorder [43], FBT in a group home setting [38], FBT started on a medical unit [39], and FBT combined with medication [42].…”

“…Biochemical side effects were closely monitored and were felt to be more related to refeeding processes than to medication [141]. Thirteen case reports (Table 24) have also been published [42,[143][144][145][146][147][148][149][150][151][152][153][154]. Pisano and colleagues [143] reported on five cases of adolescents with AN treated with 2.5 to 7.5 mg of olanzapine.…”

Antipsychotics in the Treatment of Children and Adolescents with Anorexia Nervosa: A Systematic Review

“…In 9 months, eating disorder preoccupations or rituals reduced. Some differences were noted: the twin treated with olanzapine started expressing hunger at mealtimes, and she also regained her normal eating pattern; in the end, twin B was remarkably weight restored at 99.9% IBW, while twin A had yet to weight restore at 84.4% IBW [ 30 ].…”

“…In the other papers, anecdotal weight gain and psychopathology improvements were reported, especially in anxiety [ 20 , 23 , 24 , 25 ], depression [ 20 , 24 ], obsessions and compulsions [ 23 , 25 , 27 , 30 ].…”

“…No clear-cut, olanzapine-related adverse effects were reported by five papers [ 25 , 26 , 27 , 28 , 30 ]. A severe side effect was reported in a sole case report where the onset of Neuroleptic neuroleptic malignant syndrome after two days of treatment is described [ 31 ].…”