NOT FOR REPRINT 70 • P SYCHOPHARMACOLOGY B ULLETIN: Vol. 43 · No. 4 Efficacy of High-Dose Aripiprazole for Treatment-Resistant Schizoaffective Disorder: A Case Report By Omer Saatcioglu, Sevda Gumus, Kirkor Kamberyan, Medaim Yanik Drs. Saatcioglu, MD, Gumus, MD, Kamberyan, MD, Yanik, MD, Bakirkoy Research and Training Hospital for Psychiatry, Neurology and Neurosurgery, Istanbul, Turkey. To whom correspondence should be addressed: Dr. Omer Saatcioglu, MD, Atakoy, 9. Kısım, A5-A Blok, Kat 12, Daire: 61, 34750, Istanbul, Turkey. Phone: +90 212 6615873; E-mail: osaatcioglu@superonline.com ABSTRACT ~ Aripiprazole is an atypical neuroleptic with a unique mechanism of action. According to the package insert, the maximum recommended dose for aripiprazole is 30 mg/day. In clinical practice, off-label prescribing of medications, including the use of doses that exceed the manufacturer’s recommendations, is not uncommon. Most premarket- ing studies are designed principally to demonstrate safety, efficacy, and tolerability and often exclude many patients who are treated after a drug has been released.To report a case with treatment-resistant schizoaffective disorder in which a patient tolerated and responded to high-dose aripiprazole; an objective is to discuss the use of aripiprazole dosages at higher than those recommended in the product’s labelling. Psychopharmacology Bulletin. 2010;43(4):70–72. INTRODUCTION Aripiprazole is an atypical neuroleptic with a unique mechanism of action. Rather than antagonizing the D2 receptor, aripiprazole appears to be a D2 par- tial agonist and selective agonist. 1 Aripiprazole is also a partial agonist at the 5-HT1A receptor, and like the other atypical antipsychotics displays an antago- nist profile at the 5-HT2A receptor. 2 Aripiprazole has moderate affinity for his- tamine and -adrenergic receptors and for the serotonin transporter, and no appreciable affinity for cholinergic muscarinic receptors. Aripiprazole also acts as a 5-HT2C partial agonist, which may underlie the minimal weight gain seen in the course of therapy. D2 and D3 receptor occupancy levels are high, with aver- age levels ranging between 71% at 2 mg/day to 96% at 40 mg/day. According to Key Words: schizoaffective disorder, aripiprazole COMPLICATED CASE HISTORIES SAATCIOGLU 1/7/11 6:46 PM Page 70