How Dosing of Ziprasidone in a State Hospital System Differs From Product Labeling

Background: The purpose of this article is to review the utilization and dosing of ziprasidone in a state hospital system and to compare the dosing to dosing recommendations contained in product labeling that suggest a starting dose of 40 mg/day and a target dose range of 40 to 160 mg/day for schizophrenia.

Method: Dosing of ziprasidone was examined from the time when it was first marketed in 2001 up to and including calendar year 2006 using a database that contains patient information and drug prescription information for every inpatient within the adult civil facilities of the New York State psychiatric hospital system operated by the New York State Office of Mental Health. Supporting evidence for a therapeutic dose response for ziprasidone was examined by conducting a PubMed search for the period January 1, 1990, to June 1, 2008, identifying English-language articles related to ziprasidone dose in schizophrenia using the search terms ziprasidone, dose, and schizophrenia.

Results: Although the highest efficacious dose of ziprasidone recommended in the manufacturer’s product label is 160 mg/day, the mean dose of ziprasidone prescribed among patients hospitalized in New York State in calendar year 2006 and receiving antipsychotic medication (N’ ‰=’ ‰7154) was 179 mg/day (N’ ‰=’ ‰709), with 51.6% receiving doses in excess of 160 mg/day (N’ ‰=’ ‰366). Patients discharged on treatment with ziprasidone (N’ ‰=’ ‰189) received a mean dose of 206 mg/day. Patients with schizophrenia with a history of prior state hospital admission were more likely to receive doses greater than 160 mg/day. Clinicians in hospitals with the highest prescribing rates for ziprasidone were more likely to prescribe ziprasidone in excess of 160 mg/day. The initial dose on the first day for new starts on treatment with ziprasidone was 91 mg/day (N’ ‰=’ ‰112). Published anecdotal reports describe the use of ziprasidone in excess of 160 mg/day and up to 640 mg/day among patients not responding to lower doses, but, currently, there are no published reports from double-blind randomized clinical trials establishing the utility of this high-dose treatment strategy.

Conclusions: Dosing of ziprasidone in a large state hospital system is higher than what has been established in the registration program for schizophrenia. Although there is anecdotal evidence describing the use of ziprasidone in excess of 160 mg/day, controlled clinical trials are needed to determine if these higher doses are more effective.