RESUMO
OBJECTIVES: Currently, there are three monotherapy drugs approved by the United States Food and Drug Administration (FDA) for use in intrathecal drug delivery systems (IDDS): morphine, ziconotide, and baclofen. In practice, use includes alternate drugs, drug combinations, and drug concentrations. There is a paucity of real-world data examining prescription patterns for IDDS. Our analysis explores a one-year sample of prescription intrathecal (IT) medications from a large pharmaceutical data base to characterize medication usage in IDDS. MATERIALS AND METHODS: Data were provided by an accredited pharmacy as a deidentified data base of IT drug prescriptions. Statistical analyses included rates of monotherapy vs combination therapies, frequencies of various IT prescriptions, use of on- vs off-label medications, and opioid vs nonopioid formulations. RESULTS: Data were extracted from February 1, 2021 to February 14, 2022. No patients were excluded. The initial sample comprised 49,917 individual IT prescriptions for 32,784 patients. Monotherapies constituted 55.0% of all prescriptions (27,475/49,917). Of these, 23,257 prescriptions (84.6%) were opioid based, with the most common medications being morphine (46.5%), hydromorphone (39.4%), and fentanyl (13.5%). Although 29.3% of all prescriptions were for one of the FDA-approved medications, only 7.9% used FDA-approved concentrations; 9865 patients underwent ≥one prescription change in the study period-16.7% of whom were initially prescribed medications that met the approved, on-label indications for the pump before being switched to off-label concentrations or combinations to address clinical needs. CONCLUSIONS: Despite the prevalence of IDDS for managing chronic, intractable pain, minimal data exist on real-world prescription practices. Our study found that FDA-approved IT formulations accounted for the minority of prescriptions, indicating significant practice variation, with off-label prescriptions being common.