Managing Weight Gain During Antipsychotic Treatment: What New Research Shows
Antipsychotic medications are an important part of treatment of Schizophrenia and Bipolar Affective Disorder. However, some people experience significant weight gain and changes in their metabolic health while taking these medications. These side effects should not be dismissed as simply cosmetic. Weight gain can increase the risk of physical health conditions and may also affect self-esteem, quality of life and a person’s willingness to continue taking medication.
A 2026 systematic review and network meta-analysis (Stogios et al.,2026) examined medications that may help manage weight gain in people with Schizophrenia and Bipolar Affective Disorder who are already receiving antipsychotic treatment. The findings provide an update overview of both established and emerging treatment options.
Why Can Antipsychotic-Associated Weight Gain Be Concerning?
Some antipsychotic medications can affect appetite, energy use, glucose regulation and the way the body stores fat. The degree of weight change can vary considerably between medications and between individuals. In addition to changes in body weight, antipsychotic treatment may be as associated with
- Increased waist circumference
- Changes in blood glucose or insulin sensitivity
- Altered cholesterol and triglycerides
- An increased risk of type 2 diabetes and cardiovascular disease
Weight gain may also cause distress, reduce self-esteem and contribute to a poorer quality of life. For some people, concern about these side effects can make it more difficult to continue medication consistently. This is why physical health monitoring is an important part of psychiatric care.
What Did The Study Examine?
The review examined 95 clinical trials involving 5,898 participants and 39 different pharmacological interventions. The researchers examined treatments used to reduce existing weight gain in adults with Schizophrenia and Bipolar Affective Disorder who were already taking antipsychotic medication. The study did not examine medications started at the same time as an antipsychotic to prevent weight gain.
The primary outcome was change in body weight compared with placebo. The researchers also considered changes in measures such as body mass index, waist circumference, blood glucose, cholesterol and the proportion of participants who achieved clinically meaningful weight loss.
Which Treatments Were Associated with Weight Reduction?
The review found that several medications were associated with greater than average weight reductions than placebo.
The treatments supported by the strongest available evidence were
- Semaglutide, with an average difference of 10.98 kilograms
- Liraglutide, with an average difference of 5.43 kilograms
- Topiramate, with an average difference of 3.95 kilograms
- Metformin, with an average difference of 3.86 kilograms
These findings were rated as having moderate certainty. Metformin was the most extensively studied treatment, while the evidence for newer medication such as semaglutide was based on a smaller number of trials. Other medications were also associated with weight reduction, but the certainty of the evidence was lower. These findings may change as more research become available.
What Counts as Clinically Meaningful Weight Loss?
Researchers often consider a reduction of at least 5% of a person’s starting body weight to be clinically meaningful because it may be associated with improvements in metabolic health. Only 8 trials included in the review reported this outcome. Within this smaller group, semaglutide and metformin were associated with a greater likelihood of achieving weight loss of at least 5% compared to the placebo.
However, these results should be interpreted carefully. The finding for semaglutide was based on one trial reporting this outcome, and the estimate had a wide range of uncertainty.
Do The Findings Mean GLP-1 Medications Are Suitable for Everyone?
Semaglutide and liraglutide belong to a group of medications known as glucagon-like-peptide-1 (GLP-1) receptor agonists. These treatments have become increasingly prominent in the management of diabetes and obesity.
The review suggests that their weight reducing effects may also extend to some people experiencing antipsychotic-associated weight gain. However, this does not mean that these medications are automatically appropriate for everyone taking an antipsychotic. Treatment decisions may depend on:
- The antipsychotic being taken
- The amount and timing of weight gain
- Existing medical conditions
- Other medications
- Possible adverse effects
- Access and affordability
- The person’s individual treatment goals.
Further long-term studies are also needed to better understand their ongoing effectiveness and safety in people with Schizophrenia and Bipolar Affective Disorder.
Why Does Metabolic Monitoring Remain Important?
The study supports the growing recognition that metabolic health should be considered alongside psychiatric symptoms when planning antipsychotic treatment.
Monitoring may include measurement of:
- Weight and waist circumference
- Blood pressure
- Blood glucose or HbA1c
- Cholesterol and triglyceride levels
- Changes in appetite, activity or other relevant symptoms
Identifying changes early allows the person and their treating psychiatrist to consider appropriate responses before metabolic problems become more established. Lifestyle and behavioural strategies may remain valuable, but they may not be sufficient for everyone. Some people may benefit from additional pharmacological treatment as part of a broader and individualised care plan.
Speak With Your Psychiatrist Before Making Medication Changes
People who are concerned about weight gain or other physical changes should discuss these concerns with their psychiatrist. Antipsychotic medication should not be reduced, stopped or changed without medical guidance. Sudden or unsupported changes can increase the risk of psychiatric symptoms returning or becoming more severe. Instead, a psychiatrist can consider the potential benefits and risks of different approaches, organise appropriate metabolic monitoring and work with the person to develop a treatment plan that supports both mental and physical health.
A More Complete Approach to Schizophrenia Care
Managing Schizophrenia involves more than reducing psychiatric symptoms. It also means recognising and responding to the physical health effects that can accompany the illness and its treatment. This new research suggests that several medications may help manage antipsychotic-associated weight gain. However, the most appropriate option will depend on the individual, and further long-term evidence is still needed.
Early monitoring, open discussion and individualised treatment can help ensure that concerns about weight and metabolic health are addressed as part of a comprehensive psychiatric care.
Eastern Suburbs Psychiatry provides specialised care for adults experiencing Schizophrenia and related psychiatric concerns in Darlinghurst, Sydney. To enquire about an appointment to see a Sydney psychiatrist for an individualised treatment plan, click here.