Characterizations of long-term oxycodone/acetaminophen prescriptions in veteran patients.

BACKGROUND: Long-term management of chronic pain with opioids may be stable over time or may be complicated by problematic dose increases, drug dependencies, and toxic effects. To determine clinical contexts in which stability or problems may occur, we examined the pharmacologic and clinical correlates of long-term prescriptions of oxycodone/acetaminophen, a commonly prescribed short-acting opioid formulation.

METHODS: We analyzed linked, archival outpatient pharmacy and clinical databases from the New England Veterans Integrated Service Network between January 1, 1998, and June 30, 2001. Durations, doses, and dose changes of oxycodone/acetaminophen prescriptions and concurrent use of long-acting opioids, benzodiazepines, tricyclic antidepressants, and anticonvulsants were determined.

RESULTS: In aggregate, 2195 patients (31% with cancer diagnoses per the International Classification of Diseases, Ninth Revision, Clinical Modification) received oxycodone/acetaminophen for more than 9 months at a mean prescribed daily dose of 3.9 tablets per day (range, 0.5-13.0 tablets per day) with minimal changes in daily prescribed mean dose over time. Patients with cancer were more likely than other patients to receive concurrent long-acting opioids. For patients without cancer, a higher mean daily dose was associated with duration, older age, human immunodeficiency virus (HIV) and/or AIDS, and with prescribed benzodiazepines and long-acting opioids; concurrent benzodiazepine prescriptions were associated with anticonvulsant prescriptions and with psychogenic pain and alcohol abuse and/or dependence diagnoses.

CONCLUSIONS: In veteran patients who received long-term oxycodone/acetaminophen prescriptions, mean daily doses were typically modest and stable, likely reflecting a selection of patients with successful, long-term management. Among patients without cancer, however, associations of higher oxycodone/acetaminophen doses with benzodiazepine prescriptions, psychogenic pain, alcohol abuse, and HIV/AIDS may portend opioid prescription management problems.