Atypical antipsychotics (AT) and stress are related to weight gain in individuals with severe mental illness. This cross-sectional study examines AT use, stressful life events, and baseline weight in a sample of youth at clinical high risk for psychosis. Results showed that dependent and desirable life events moderated the relationship between AT use and weight after controlling for demographic factors and selective serotonin reuptake inhibitor antidepressant (AD) use. The relation of AD and weight was explored as a secondary analysis and showed no relation between AD use and weight. Further, stress did not moderate the relationship between AD medication and weight after controlling for antipsychotic use. Results suggest that stress exposure may exacerbate the relationship between ATs and increased weight in clinical high-risk populations. Findings have implications for the development of interventions to address psychosocial factors that worsen or buffer the adverse effects of antipsychotic medication on weight
