More than 90 percent of antipsychotic prescriptions are written for second generation medications, despite the fact they are more expensive than the first generation agents used to treat schizophrenia. The majority of clinicians have traditionally believed that the newer antipsychotics are more effective and better tolerated than older agents, and many experts argued that these advantages justified the difference in cost.

Robert Rosenheck, M.D., of Yale University, and colleagues analyzed costs and quality-of-life factors associated with each of the five medications used in Phase 1 of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) trial—olanzapine, quietapine, risperidone, ziprasidone, and perphenazine. They found that total monthly health costs, a figure that includes both average medication costs and inpatient and outpatient costs, were up to 30 percent lower for those taking the perphenazine than for those taking the second generation medications. In addition, the researchers found no statistically significant difference in overall effectiveness between perphenazine and the second generation antipsychotics, with regard to symptom relief and side effect burden.

Still, several conditions of CATIE limit any firm conclusions about perphenazine's perceived advantages. Not all patients respond the same to different medications. In addition, the study lasted 18 months—long enough to determine how patients respond to and initially tolerate the drugs, but not long enough to consider some serious long-term side effects, such as development of the movement disorder tardive dyskinesia (TD), diabetes, cardiovascular problems, or other medical conditions that can develop even years after a patient with chronic schizophrenia starts taking an antipsychotic medication.; Source: National Institute of Mental Health