Out-of-plan pharmacy use by members of a managed care organization.

Background: Bargain generic programs have proliferated rapidly since 2006. Little is known about the use of these programs. The purpose of this study was to assess the rate and characteristics of prescriptions written in a managed care organization (MCO) to an out-of-plan pharmacy (OOPP).

Methods: This retrospective health services investigation examined characteristics of patients in an MCO who did and did not have a prescription written to an OOPP from October 1, 2006 through September 30, 2010, and patients who had a prescription transferred to an OOPP in September 2008 (only month with data available). Descriptions of the longitudinal rate of OOPP use, OOPP patient and medication characteristics, and OOPPs where prescriptions were transferred are reported. Patient characteristics independently associated with an OOPP prescription were analyzed with logistic regression modeling.

Results: A total of 10,353,283 prescriptions were included. The monthly rate of OOPP usage during the study period increased from 1.5% to 5.2% and then stabilized at around 5%. Prescriptions written to an OOPP were more likely to be for chronic disease states. Patient age and MCO termination were associated with having a prescription written to an OOPP; whereas increasing medication purchases, a drug benefit, and a health maintenance organization plan type were associated with not having a prescription written to an OOPP. More than 80% of transferred prescriptions went to an OOPP with a bargain generic program.

Conclusion: The rate of OOPP prescriptions increased rapidly over the study period. Prescriptions written to an OOPP were predominantly for chronic diseases. Further research is warranted to assess if OOPP use results in reduced quality of health care system oversight or compromises patient health.