Amantadine is an antiviral agent effective against influenza A infection [Jefferson et al. 2006] as well as an antiparkinsonian drug used for the treatment of extrapyramidal side

effects associated with antipsychotic drugs [Silver and Geraisy, 1996]. It has been studied for weight reducing effects in those with antipsychotic-induced weight gain, based on its ability to modify dopamine and serotonin neurotransmission. In an animal study, there was dose-dependent appetite loss following administration of amantadine Inhibitors,research,lifescience,medical through the lateral hypothalamus, possibly through release of dopamine and serotonin in the nucleus accumbens and lateral hypothalamus [Baptista et al. 1997], although it failed to prevent sulpiride-induced weight gain completely. As the weight gain pattern is different for olanzapine as compared

with other S3I-201 clinical trial atypical antipsychotics and it is one of the most commonly used antipsychotics, we conducted a systematic Inhibitors,research,lifescience,medical review and meta-analysis with an objective to determine the effects of amantadine for reducing or preventing weight gain associated with olanzapine. Methods In our systematic review and meta-analysis, we adhered to the recent update of preferred reporting items for Inhibitors,research,lifescience,medical systematic reviews and meta-analyses (PRISMA) guidelines [Moher et al. 2009]. The flow of studies is summarized in Figure 1. Figure Inhibitors,research,lifescience,medical 1. PRISMA 2009 flow diagram. Data sources and search strategy Studies were identified using online searches of PUBMED/MEDLINE and the Cochrane database (CENTRAL). Also, websites recording trial information such as ClinicalTrials.gov, Controlled-trials.com, and Clinicalstudyresults.org were searched for relevant studies. Searches were conducted using combination of terms ‘atypical Inhibitors,research,lifescience,medical antipsychotics’, ‘olanzapine’, ‘body weight gain’, ‘obesity’ and ‘amantadine’. We inspected reference list of all identified studies, including existing reviews

for relevant citations. The search was restricted to publications in the English language. Study selection: inclusion criteria One reviewer (SKP) initially not evaluated the abstracts from the literature search. The following criterion was used to identify the studies: randomized, double-blind clinical trials comparing amantadine with placebo for olanzapine-induced weight gain; outcome measures include body weight; study duration of at least 12 weeks. Data extraction Two reviewers (SKP and PSVNS) decided, independently, whether individual studies met the inclusion criteria. We used a standardized form, and extracted data which included patient and study characteristics, outcome measures and study results. Assessment of methodological quality of studies The methodological quality of included trials in this review was assessed using the Jadad scale [Jadad et al. 1996].