Drug-related problems among hospitalized cancer pain patients: an investigative single-arm intervention trial

Background To evaluate the characteristics of drug-related problems (DRPs) in cancer pain patients, and to identify the impact of pharmacists' intervention in cancer pain associated DRPs. Methods In this investigative, single-arm intervention study, clinical pharmacists identified DRPs in cancer pain patients and provided interventions based on medication information, direct patient-pharmacist interview, and ward rounds with multi-disciplinary team (MDT). Types and causes of DRPs, interventions, acceptance and outcome were sorted based on Pharmaceutical Care Network Europe (PCNE) DRP classification V9.0, which includes 3 primary domains for problems, 9 for causes, 5 for interventions, 3 for acceptance, and 4 for DRPs status. Results Totally, 42 cancer pain patients were enrolled, and 47 DRPs in 33 (78.6%) patients were identified by clinical pharmacists. The major type of DRPs was treatment effectiveness (30; 63.8%) and treatment safety (17; 36.2%). For the "treatment effectiveness" category, the "effect of drug treatment not optimal" was dominant category (27/30; 90%). A total of 66 DRP causes were identified, and most of DRPs were caused by "drug selection" (27; 40.9%) and "dose selection" (16; 24.2%). Within the "drug selection" category, "no or incomplete drug treatment in spite of existing indication" was dominant category (25/27; 92.6%). According to DRPs, 159 interventions were provided by clinical pharmacists and 99.4% of interventions were accepted by prescribers or patients. Finally, 44 (93.6%) DRPs were solved. Conclusions In cancer pain patients, insufficient pain control mainly caused by inappropriate selection and dosage of analgesics. Clinical pharmacists' interventions dramatically ameliorate these problems and bring about positive effects in cancer pain pharmacotherapy.