Lurasidone as add-on to fluoxetine in obsessive-compulsive disorder with comorbid restrictive anorexia: a case report

: Obsessive-compulsive disorder (OCD) is a pervasive disabling disorder that may overlap with other psychiatric conditions, including anorexia nervosa. Recent guidelines recommend low doses of second-generation antipsychotics as add-on therapy to selective serotonin reuptake inhibitors (SSRIs) for those patients presenting OCD who display residual symptomatology. Here we report a clinical case of a 45-years-old woman affected by severe OCD in comorbidity with anorexia nervosa, restrictive type (AN-r), treated with fluoxetine (titrated up to 40 mg/day) in augmentation with low doses of lurasidone (37 mg/day). At baseline and during a 6 months-follow-up we administered Clinical Global Impression-Severity, Symptom Checklist-90 items, Y-BOCS-II (Yale-Brown Obsessive Compulsive Scale) and EDI-3 (Eating Disorder Inventory). After 1 month of augmentation treatment, a clinically significant response was observed on obsessive symptoms at Y-BOCS-II (≥35% Y-BOCS reduction) and eating symptomatology at EDI-3. Full remission was reported after 3 months (Y-BOCS scoring ≤14) (P < 0.01). Further longitudinal and real-world effectiveness studies should be implemented to confirm these novel results, to investigate the potential of lurasidone as add-on strategy to SSRI in poor responder OCD patients, including treatment-resistant-OCD (tr-OCD), as well as in improving eating disorder symptomatology, whereas there is comorbidity with AN-r.