Federal prosecutors allege two nursing homes in California have "persistently and severely overmedicated elderly and vulnerable residents." Antipsychotic drugs like risperidone, also known as Risperdal, can be dangerous for elderly people, but are frequently prescribed to nursing home patients. JB Reed/Bloomberg via Getty Images hide caption

itoggle caption JB Reed/Bloomberg via Getty Images

Seroquel, made by AstraZeneca, was the most prescribed of the atypical antipsychotics scrutinized in a federal audit of nursing home claims. Anonymous/AP hide caption

itoggle caption Anonymous/AP