Prescribing patterns and purchasing costs of long-acting opioids over nine years at an academic oncology hospital

Abstract

The prescribing patterns and purchasing costs of long-acting opioids over nine years at an academic oncology hospital were studied. Data were collected for doses of transdermal fentanyl, methadone (all routes of administration), and oral sustained-release morphine and oxycodone dispensed for individual inpatient use for the month of October for each year between 1996 and 2004. The dates included in the retrieval were selected to document long-acting opioid use before and after the establishment of the palliative care and rehabilitation medicine department. For each opioid the number of milligrams dispensed daily per patient was determined and converted into a morphine-equivalent daily dose (MEDD). The average wholesale price per dosing unit of each drug during each period studied was obtained from internal databases. Costs were calculated by multiplying the number of units dispensed by the average wholesale price per unit and then normalized to 1996 U.S. dollars. The mean aggregate cost for a single MEDD in a month was determined by multiplying the mean cost per MEDD for each agent by that agent's percent contribution to the total MEDDs dispensed in that month. Long-acting opioid and methadone usage increased from 1996 to 2004. Between 1996 and 2004, the mean cost of a single MEDD dropped from $0.0738 to $0.0330. During the study period, the median daily cost to treat one patient dropped from $5.96 to $2.80. Long-acting opioid use increased and cost per MEDD decreased at an academic oncology hospital between 1996 and 2004. The decreased cost of purchasing opioids was attributed to the increased proportional use of methadone.