Effect of metformin on olanzapine-induced weight gain: A 12-week randomised open-label study

Background: Olanzapine is an atypical antipsychotic used in schizophrenia and bipolar affective disorder, but it is associated with weight gain and metabolic syndrome. Metformin is known to decrease insulin resistance and abnormal glucose metabolism. Therefore, it is thought that metformin might pro...

Full description

Saved in:
Bibliographic Details
Main Authors: G. Chetan Kumar, N. Sarala, M. Mohan Reddy, H. Manjunath
Format: Article
Language:English
Published: Wolters Kluwer Medknow Publications 2025-01-01
Series:Journal of Clinical Sciences
Subjects:
Online Access:https://journals.lww.com/10.4103/jcls.jcls_62_24
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849729546199236608
author G. Chetan Kumar
N. Sarala
M. Mohan Reddy
H. Manjunath
author_facet G. Chetan Kumar
N. Sarala
M. Mohan Reddy
H. Manjunath
author_sort G. Chetan Kumar
collection DOAJ
description Background: Olanzapine is an atypical antipsychotic used in schizophrenia and bipolar affective disorder, but it is associated with weight gain and metabolic syndrome. Metformin is known to decrease insulin resistance and abnormal glucose metabolism. Therefore, it is thought that metformin might prove useful in preventing weight gain induced by olanzapine. Hence, this study was undertaken to assess the effect of metformin on body weight, body mass index (BMI), waist and hip circumference, waist-to-hip ratio, and blood glucose levels in patients receiving olanzapine and to observe their adverse effects. Methods: Sixty-five patients with schizophrenia or bipolar mania were randomly assigned for 12 weeks of treatment with olanzapine 10 mg/day plus metformin 850 mg/day (n = 33) or olanzapine alone (n = 32). Body weight, BMI, waist circumference, hip circumference, and waist-to-hip ratio were measured at baseline, weeks 4, 8, and 12. Fasting plasma glucose was estimated at baseline and end of the study. Results: 59/65 (90.8%) patients completed the study. The body weight, BMI, waist circumference, hip circumference, and waist-to-hip ratio increased in both groups but it was relatively less in patients receiving metformin along with olanzapine. In patients who received olanzapine plus metformin, weight gain of more than 7% was observed in 43.3%, and 86.2% in those who received only olanzapine, the difference in this parameter was statistically significant (P = 0.001). Fasting plasma glucose had decreased significantly with olanzapine plus metformin at week 12. Conclusion: The metformin plus olanzapine group patients had relatively less weight gain compared to those who received only olanzapine.
format Article
id doaj-art-5151de8b7ca54db59e4c16f68f1a4b82
institution DOAJ
issn 2468-6859
2408-7408
language English
publishDate 2025-01-01
publisher Wolters Kluwer Medknow Publications
record_format Article
series Journal of Clinical Sciences
spelling doaj-art-5151de8b7ca54db59e4c16f68f1a4b822025-08-20T03:09:12ZengWolters Kluwer Medknow PublicationsJournal of Clinical Sciences2468-68592408-74082025-01-01221111710.4103/jcls.jcls_62_24Effect of metformin on olanzapine-induced weight gain: A 12-week randomised open-label studyG. Chetan KumarN. SaralaM. Mohan ReddyH. ManjunathBackground: Olanzapine is an atypical antipsychotic used in schizophrenia and bipolar affective disorder, but it is associated with weight gain and metabolic syndrome. Metformin is known to decrease insulin resistance and abnormal glucose metabolism. Therefore, it is thought that metformin might prove useful in preventing weight gain induced by olanzapine. Hence, this study was undertaken to assess the effect of metformin on body weight, body mass index (BMI), waist and hip circumference, waist-to-hip ratio, and blood glucose levels in patients receiving olanzapine and to observe their adverse effects. Methods: Sixty-five patients with schizophrenia or bipolar mania were randomly assigned for 12 weeks of treatment with olanzapine 10 mg/day plus metformin 850 mg/day (n = 33) or olanzapine alone (n = 32). Body weight, BMI, waist circumference, hip circumference, and waist-to-hip ratio were measured at baseline, weeks 4, 8, and 12. Fasting plasma glucose was estimated at baseline and end of the study. Results: 59/65 (90.8%) patients completed the study. The body weight, BMI, waist circumference, hip circumference, and waist-to-hip ratio increased in both groups but it was relatively less in patients receiving metformin along with olanzapine. In patients who received olanzapine plus metformin, weight gain of more than 7% was observed in 43.3%, and 86.2% in those who received only olanzapine, the difference in this parameter was statistically significant (P = 0.001). Fasting plasma glucose had decreased significantly with olanzapine plus metformin at week 12. Conclusion: The metformin plus olanzapine group patients had relatively less weight gain compared to those who received only olanzapine.https://journals.lww.com/10.4103/jcls.jcls_62_24atypical antipsychoticsmetforminolanzapineweight gain
spellingShingle G. Chetan Kumar
N. Sarala
M. Mohan Reddy
H. Manjunath
Effect of metformin on olanzapine-induced weight gain: A 12-week randomised open-label study
Journal of Clinical Sciences
atypical antipsychotics
metformin
olanzapine
weight gain
title Effect of metformin on olanzapine-induced weight gain: A 12-week randomised open-label study
title_full Effect of metformin on olanzapine-induced weight gain: A 12-week randomised open-label study
title_fullStr Effect of metformin on olanzapine-induced weight gain: A 12-week randomised open-label study
title_full_unstemmed Effect of metformin on olanzapine-induced weight gain: A 12-week randomised open-label study
title_short Effect of metformin on olanzapine-induced weight gain: A 12-week randomised open-label study
title_sort effect of metformin on olanzapine induced weight gain a 12 week randomised open label study
topic atypical antipsychotics
metformin
olanzapine
weight gain
url https://journals.lww.com/10.4103/jcls.jcls_62_24
work_keys_str_mv AT gchetankumar effectofmetforminonolanzapineinducedweightgaina12weekrandomisedopenlabelstudy
AT nsarala effectofmetforminonolanzapineinducedweightgaina12weekrandomisedopenlabelstudy
AT mmohanreddy effectofmetforminonolanzapineinducedweightgaina12weekrandomisedopenlabelstudy
AT hmanjunath effectofmetforminonolanzapineinducedweightgaina12weekrandomisedopenlabelstudy