Random drugsThe vast majority of people — over 90% — with schizophrenia fail to stay on their prescribed antipsychotic medications after one year.

Most people with this disorder are prescribed medication for years at a time as a method for reducing the effect of the disorder’s primary symptoms — hallucinations and delusions.

The researchers from the University of Maryland School of Pharmacy studied 5,898 people with schizophrenia from Maryland who were on Medicaid. The subjects were placed on one of the following atypical antipsychotic medications: aripiprazole (Abilify); olanzapine (Zyprexa); quetiapine (Seroquel); risperidone (Risperdal); and ziprasidone (Geodon).

Quetiapine (Seroquel) was associated with significantly higher hazard of discontinuation than olanzapine (Zyprexa), which was the study’s reference drug.

Otherwise, discontinuation rates were high at one-year follow-up and did not differ significantly for any of the drugs studied.

Newer antipsychotic medications are touted as having more tolerable side effects. Drug makers thought by offering drugs with more tolerable side effects than older antipsychotic medications, prescription adherence rates would rise.

Men, people who were older, and people who were already on another medication were significantly less likely to discontinue their medication than others in the study. People who had a previous hospitalization were significantly more likely to discontinue their prescribed medication in the study.

The study will appear in an upcoming issue of Schizophrenia Research and is consistent with previous findings in this area.

Source: Mullins CD, Obeidat NA, Cuffel BJ, Naradzay J, Loebel AD. (2007). Risk of discontinuation of atypical antipsychotic agents in the treatment of schizophrenia. Schizophr Res. 2007 Jun 25.