GLP-1 drug exenatide prevents olanzapine-related weight gain in psychiatric patients
In a double-blind RCT, exenatide prevented olanzapine-associated weight gain (-0.5 kg vs +2.6 kg with placebo over 16 weeks) without affecting mood or psychotic symptoms.
Quick Facts
What This Study Found
Exenatide vs placebo over 16 weeks: -0.5 kg (-0.6%) vs +2.6 kg (+2.8%), both p<0.01. Exenatide was well-tolerated. No clinically meaningful differences in mood or psychotic symptoms between groups.
Key Numbers
Exenatide: -0.5 kg (-0.6%) vs placebo: +2.6 kg (+2.8%), both P < 0.01. 16-week double-blind trial. Most common side effects: GI symptoms and headaches. No clinically meaningful changes in mood or psychotic symptoms.
How They Did This
Randomized, double-blind, placebo-controlled trial (NCT00845507) in adults with stable major mood or psychotic disorders on olanzapine, treated for 16 weeks.
Why This Research Matters
Olanzapine is one of the most effective antipsychotics but causes severe weight gain that leads to metabolic syndrome, diabetes, and medication discontinuation. An effective, psychiatrically safe weight management option could improve both physical health and medication adherence in this vulnerable population.
The Bigger Picture
Antipsychotic-induced weight gain is a major clinical problem affecting millions of psychiatric patients. This trial demonstrates that GLP-1 drugs can be safely used alongside psychiatric medications, opening a new management strategy for metabolic complications in mental health care.
What This Study Doesn't Tell Us
Relatively small sample size and short 16-week duration. Only studied exenatide (less potent than semaglutide). Only studied olanzapine; results may not generalize to other antipsychotics. Primarily assessed weight prevention rather than weight loss.
Questions This Raises
- ?Would more potent GLP-1 agonists like semaglutide produce greater weight loss in psychiatric patients?
- ?Can GLP-1 drugs improve metabolic syndrome in patients already obese from antipsychotic use?
- ?Should GLP-1 drugs be routinely co-prescribed with weight-gaining antipsychotics?
Trust & Context
- Key Stat:
- 3.1 kg difference in 16 weeks Exenatide patients lost weight while placebo patients gained, with no worsening of psychiatric symptoms
- Evidence Grade:
- Randomized, double-blind, placebo-controlled trial—highest quality study design. Moderate sample size and duration. Strong evidence for safety and efficacy in this population.
- Study Age:
- Published in 2025; addresses a growing clinical need as GLP-1 drug use expands into psychiatric populations.
- Original Title:
- A double-blind, placebo-controlled trial of exenatide for the treatment of olanzapine-related weight gain in obese and overweight adults.
- Published In:
- Journal of affective disorders, 382, 116-122 (2025)
- Authors:
- Patino, Luis R, Strawn, Jeffrey R, Adler, Caleb M, Blom, Thomas J, Welge, Jeffrey A, DelBello, Melissa P
- Database ID:
- RPEP-12986
Evidence Hierarchy
Participants are randomly assigned to treatment or placebo groups to test cause and effect.
What do these levels mean? →Frequently Asked Questions
Can GLP-1 drugs be used with psychiatric medications?
This trial shows exenatide is safe and effective alongside olanzapine, with no worsening of mood or psychotic symptoms. It prevented the significant weight gain typically seen with olanzapine, suggesting GLP-1 drugs can be an important tool for managing antipsychotic side effects.
Why do antipsychotics cause weight gain?
Olanzapine and similar antipsychotics affect brain receptors (histamine, serotonin) that regulate appetite and metabolism, leading to increased food intake and metabolic changes. GLP-1 drugs counteract this by reducing appetite and improving metabolic function through a different pathway.
Read More on RethinkPeptides
Cite This Study
https://rethinkpeptides.com/research/RPEP-12986APA
Patino, Luis R; Strawn, Jeffrey R; Adler, Caleb M; Blom, Thomas J; Welge, Jeffrey A; DelBello, Melissa P. (2025). A double-blind, placebo-controlled trial of exenatide for the treatment of olanzapine-related weight gain in obese and overweight adults.. Journal of affective disorders, 382, 116-122. https://doi.org/10.1016/j.jad.2025.04.046
MLA
Patino, Luis R, et al. "A double-blind, placebo-controlled trial of exenatide for the treatment of olanzapine-related weight gain in obese and overweight adults.." Journal of affective disorders, 2025. https://doi.org/10.1016/j.jad.2025.04.046
RethinkPeptides
RethinkPeptides Research Database. "A double-blind, placebo-controlled trial of exenatide for th..." RPEP-12986. Retrieved from https://rethinkpeptides.com/research/patino-2025-a-doubleblind-placebocontrolled-trial
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.