Research

Mixed

Second-generation antipsychotics, particularly clozapine and olanzapine, cause significant weight gain in patients with schizophrenia, driven by increased caloric intake (orexigenic effects) and potentially altered energy expenditure.

If you are taking clozapine or olanzapine for schizophrenia, expect significant weight gain due to biological changes in hunger and food preference, not just lifestyle. This is a known side effect of the medication, not a personal failure. Proactive management with behavioral interventions and potentially switching to lower-risk medications (if clinically appropriate) is necessary.

StrongSupportsVERY_HIGH confidence
Weight gain is greatest with the second-generation antipsychotics, clozapine, and olanzapine... The etiology includes adverse effects of antipsychotics... Patients with schizophrenia have higher intake of calories in the form of high-density food and lower energy expenditure.
Peter Manu et al. · Acta Psychiatrica Scandinavica · 2015

Why this rating

Based on multiple meta-analyses, large cohort studies, and experimental models cited in the review.

Source

Weight gain and obesity in schizophrenia: epidemiology, pathobiology, and management

Peter Manu et al. · Acta Psychiatrica Scandinavica · 2015

narrative_reviewCited 283×
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