Characteristics and trends of low-dose quetiapine use in two western state Medicaid programs.

Purpose Medicaid programs are concerned about inappropriate, potentially hazardous, and costly off-label use of second-generation antipsychotics (SGAs). Several states are exploring policies aimed at managing low-dose quetiapine, commonly prescribed for off-label conditions. This study aimed to characterize longitudinal trends and patient characteristics associated with low-dose quetiapine in two state Medicaid programs. We further aimed to quantify changes in the use of quetiapine associated with a legal settlement that curtailed offlabel promotion of this product. Methods Using administrative data from two state Medicaid programs, Oregon and Colorado, we identified SGA initiators and determined patient level factors associated with receipt of low-dose SGAs. We evaluated changes in low-dose quetiapine initiation during and after a period in which quetiapine was being promoted illegally for off-label purposes. Results We identified 14763 new SGA starts during the study period. Low-dose (versus therapeutic dose) SGA use was common in both states, representing 53% to 56% of initiators. Quetiapine was the most commonly used SGA in both states and both dose ranges. Diagnoses of schizophrenia, bipolar disorder, posttraumatic stress disorder, anxiety disorder, and use of newer sedative hypnotics were associated with lower likelihood of initiating low-dose quetiapine. Initiation of low-dose quetiapine as a proportion of all SGA initiation and of all quetiapine initiation significantly declined in Oregon following suspension of off-label promotional activities. Conclusions Low-dose SGA and specifically low-dose quetiapine use remains common. Medicaid programs must set policies carefully to maximize the net safety of prescription use while optimizing disease management considering the potential for substitution effects. Copyright © 2013 John Wiley & Sons, Ltd. key words—Medicaid; drug utilization; antipsychotics; pharmacoepidemiology Received 31 May 2013; Revised 19 September 2013; Accepted 24 September 2013