Assessment of Treatment Algorithms Including Amantadine, Metformin, and Zonisamide for the Prevention of Weight Gain With Olanzapine: A Randomized Controlled Open-Label Study
J Clin Psychiatry 2012;73(2):216-223
© Copyright 2016 Physicians Postgraduate Press, Inc.
Purchase This PDF for $40.00
If you are not a paid subscriber, you may purchase the PDF.
(You'll need the free Adobe Acrobat Reader.)
Receive immediate full-text access to JCP. You can subscribe to JCP online-only ($86) or print + online ($156 individual).
With your subscription, receive a free PDF collection of the NCDEU Festschrift articles. Hurry! This offer ends December 31, 2011.
If you are a paid subscriber to JCP and do not yet have a username and password, activate your subscription now.
As a paid subscriber who has activated your subscription, you have access to the HTML and PDF versions of this item.
Click here to login.
Did you forget your password?
Still can't log in? Contact the Circulation Department at 1-800-489-1001 x4 or send email
Objective: This 22-week, open-label study, conducted between November 2006 and September 2008 in a community setting, was designed to determine if weight gain during olanzapine treatment can be prevented or mitigated with adjunctive treatment algorithms that include amantadine, metformin, and zonisamide.
Method: Outpatients with schizophrenia or schizoaffective disorder (DSM-IV-TR criteria) were randomly assigned to olanzapine alone (n = 50), olanzapine plus algorithm A (olanzapine + A [amantadine 200 mg/d with possible switches to metformin 1,000–1,500 mg/d and then to zonisamide 100–400 mg/d; n = 76]), or olanzapine plus algorithm B (olanzapine + B [metformin 1,000–1,500 mg/d with possible switches to amantadine 200 mg/d and then to zonisamide 100–400 mg/d; n = 73]). Brief weight management education was provided at baseline. The primary outcome measure was comparison of mean weight gain between olanzapine and pooled olanzapine + A and olanzapine + B results.
Results: Least squares mean ± SE weight gain was 2.76 ± 0.75 kg for olanzapine, 2.40 ± 0.65 kg for olanzapine + A, and 0.65 ± 0.63 kg for olanzapine + B. Mean weight gain during olanzapine treatment did not differ significantly from pooled results for olanzapine + A and olanzapine + B (P = .065). Participants treated with olanzapine + B experienced significantly less mean weight gain than olanzapine-treated participants (P = .036).
Conclusions: Pooled treatment algorithm results were not significantly different from olanzapine monotherapy in mitigating weight gain. However, participants who received treatment with metformin with possible progression to amantadine and then zonisamide had significantly less mean weight gain than participants treated with olanzapine alone. Progression of some participants through the algorithm indicated that a single therapy solution may not be adequate for every patient. Patients treated with olanzapine should receive regular weight monitoring.
Trial Registration: clinicaltrials.gov Identifier: NCT00401973
J Clin Psychiatry
Submitted: August 3, 2009; accepted September 28, 2010.
Online ahead of print: May 17, 2011 (doi:10.4088/JCP.09m05580).
Corresponding author: Vicki Poole Hoffmann, PharmD, Lilly USA, LLC, Lilly Corporate Center, Indianapolis, IN 46285 (email@example.com).