Why does Rexulti cause weight gain?
Key Points
Although effects can vary between patients, medicines in the atypical antipsychotic class like Rexulti are often associated with weight gain, possibly due to an increased appetite, less physical activity because of side effects like drowsiness or fatigue, and changes in metabolism.
Rexulti (brexpiprazole) is an atypical antipsychotic used to treat patients with major depressive disorder (MDD), schizophrenia, and agitation associated with dementia due to Alzheimer’s disease. Weight gain is one of the most commonly reported side effects of Rexulti in patients treated for either depression or schizophrenia.
You and your healthcare provider should check your weight on a regular basis while taking this medicine.
Depression studies
In two 6-week long studies of adults with depression, 2% to 5% of patients taking Rexulti plus an antidepressant reported at least a 7% increase in body weight, compared with 2% of patients taking an antidepressant plus a placebo (a pill that contains no medicine).
In studies of patients treated for depression with Rexulti, 4% of patients discontinued the treatment due to a weight increase. At the end of a one-year study, patients had gained an average of 3.1 kg (6.8 lb) from the start of the study. Results showed 30% of patients had a 7% or greater increase in body weight, while 4% had a 7% or greater decrease in body weight.
Schizophrenia studies
In studies of patients treated for schizophrenia, 0.6% of patients discontinued Rexulti treatment due to a weight increase. Results showed 20% of patients had a 7% or greater increase in body weight, while 10% had a 7% or greater decrease in body weight. At the end of a one-year study, patients taking Rexulti had gained an average of 2 kg (4.4 lb) from the start of the study.
In pediatric studies, 0.5% of patients 13 to 17 years of age discontinued due to weight increase. The mean increase in weight was 3.8 kg (8.4 lb). Z scores, which adjust for normal growth in a child, showed that 20% of children had an increase in age-and-gender-adjusted body weight z-score of at least 0.5 SD from baseline, a clinically significant effect.
Rexulti may lead to other metabolic side effects that are also linked with antipsychotic treatments, such as high blood sugar, type 2 diabetes, and increased lipids levels like cholesterol and triglycerides. Your doctor will monitor you for these changes.
Related questions
- What is Rexulti used for and how well does it work?
- How long does it take for Rexulti to work?
- How does Rexulti work?
Agitation associated with dementia due to Alzheimer’s studies
In patients with agitation associated with dementia due to Alzheimer’s disease, 2% of patients had at least a 7% increase in body weight at any visit compared to 0% in those taking a placebo (a pill with no medicine).
In a 12-week long extension study after the initial 12 week treatment period, there was no mean change in weight at their last study visit. Overall, 4% of patients demonstrated at least a 7% increase in body weight, and 5% showed at least a 7% decrease in body weight from baseline to last visit.
Bottom Line
Rexulti (brexpiprazole) is in a class of medicines known as atypical antipsychotics. Although your results may vary, the atypical antipsychotic class is often associated with weight gain, possibly due to changes in metabolism, an increased appetite and less physical activity because of side effects like drowsiness or fatigue.
Weight gain is one of the most commonly reported side effects of Rexulti in patients treated for either depression or schizophrenia, but not everyone gains weight. For example, at the end of a one-year study in adults being treated with Rexulti for depression (in addition to an antidepressant), patients had gained an average of 3.1 kg (6.8 lb) from the start of the study. Results showed 30% of patients had a 7% or greater increase in body weight, while 4% had a 7% or greater decrease in body weight.
This is not all the information you need to know about Rexulti (brexpiprazole) for safe and effective use. Review the full Rexulti information here, and discuss this information and any questions you have with your doctor or other health care provider.
References
- Rexulti (brexpiprazole) [product information]. Otsuka Pharmaceutical Co. Rockville, MD. 5/2024. Accessed Jan 17, 2025 at https://www.otsuka-us.com/sites/g/files/qhldwo10016/files/media/static/Rexulti-PI.pdf
- Rexulti.com. Efficacy data for Rexulti. Accessed Jan 17, 2025 at https://www.rexultihcp.com/sz/safety#adverse-reactions
- Rexulti.com. Why Rexulti. Accessed Jan 17, 2025 at https://www.rexulti.com/mdd/why-rexulti
Read next
Is obesity a major risk factor for Covid-19?
Obesity is a major risk factor for covid-19 and people who are obese are more likely than those who are not obese to contract Covid-19 at a younger age, develop severe Covid-19, require hospitalization, oxygen, mechanical ventilation, intubation, or admission into ICU, end up in hospital sooner, or die from Covid-19. Continue reading
Mounjaro vs Ozempic: Which is right for you?
Mounjaro and Ozempic are prescription medicines used alongside diet and exercise to help control blood sugar (glucose) levels in adults with type 2 diabetes. Ozempic is also approved to lower the risk of a major cardiovascular event (like a heart attack or stroke) in patients with type 2 diabetes, as well as to reduce the risk of worsening kidney disease and heart-related death in patients with type 2 diabetes. Mounjaro has not yet received these indications, although studies are ongoing.
In a large, 2024 retrospective study in adults with overweight or obesity and treated for type 2 diabetes, Mounjaro led to at least a 5% weight loss within one year in 81.8% of adults compared to 66.5% of those using Ozempic. Continue reading
Zepbound vs Mounjaro: Comparison Guide for Weight Loss and Diabetes Treatment
Zepbound and Mounjaro contain the same active ingredient (tirzepatide) and both are made by Eli Lilly and Company, but they have different FDA approved uses and insurance coverage. Zepbound is approved for chronic weight management and obstructive sleep apnea (OSA) and Mounjaro is approved for type 2 diabetes.
Continue readingSee also:
Related medical questions
- Ozempic Side Effects to Watch For
- Why am I not losing weight on Mounjaro?
- Ozempic Mounjaro Wegovy & Zepbound: Weight Loss Compared
- Wegovy vs Ozempic: Which is Right for You?
- How long does it take for Ozempic to work?
- How long until I'll lose weight with Wegovy?
- Does levothyroxine cause weight gain or loss?
- Which GLP-1 drug is best for weight loss?
- Do Ozempic, Wegovy, Mounjaro & Zepbound cause hair loss?
- How does Ozempic work for weight loss?
- Tirzepatide vs semaglutide: How do they compare?
- Does Wellbutrin XL/SR cause weight gain or loss?
- Why does Lexapro cause weight gain? Complete Patient Guide
- Does Ozempic need to be refrigerated?
- Does Lyrica (pregabalin) cause weight gain?
- How much is Zepbound with or without insurance?
- What happens when you stop taking Ozempic?
- Does gabapentin cause weight gain?
- Does Zoloft (sertraline) cause weight gain?
- Will my insurance cover the cost of Ozempic?
- How long does it take for Zepbound to work?
- How does Mounjaro Work for Weight Loss?
- Saxenda vs Ozempic: For Weight Loss?
- Does Prozac cause weight gain or loss?
- How effective is Topamax (topiramate) for weight loss?
- Can you get tirzepatide from a compounding pharmacy?
- Why am I not losing weight on Ozempic?
Drug information
- Rexulti Information for Consumers
- Rexulti prescribing info & package insert (for Health Professionals)
- Side Effects of Rexulti (detailed)
- Rexulti user reviews (502)
Related support groups
- Rexulti (19 questions, 60 members)
- Weight Loss (Obesity/Overweight) (875 questions, 1,514 members)
- Major Depressive Disorder (540 questions, 1,392 members)
- Schizophrenia (105 questions, 328 members)
- Agitation Associated with Dementia Due to Alzheimer’s Disease (2 questions, 4 members)