Indermitte J, Beutler M, Bruppacher R, Meier C R, Hersberger K E
Department of Pharmaceutical Sciences, Institute of Clinical Pharmacy, University of Basel, Basel, Switzerland.
J Clin Pharm Ther. 2007 Apr;32(2):133-42. doi: 10.1111/j.1365-2710.2007.00802.x.
Drug-interaction alert systems are commonly used in community pharmacies to identify potential drug-drug interactions. However, depending on the software default setting, pharmacists may override alerts because they are too numerous. We explored the handling of drug-interaction alerts by community pharmacies in Switzerland.
Data were collected by 15 trained pharmacy students in 15 Swiss community pharmacies. The medication history and the drug-interaction alerts of 600 patients who had >or=2 drugs on prescription were assessed, and the pharmacists in charge were interviewed about their management of drug-interaction alerts.
In the 15 pharmacies studied, the computer systems were programmed to flag only 'severe' drug interactions in four, 'severe or moderate' in six or 'severe, moderate or minor' in five pharmacies. The median frequency of drug-interaction alerts increased with decreasing default severity level from 0.5 to 40, respectively, to 76 per 40 patient visits and pharmacy. Because of these default settings, 277 (35 x 2%) of 787 potential drug-interaction alerts on new or repeated prescriptions were overridden by the computer systems. Only 256 (32 x 5%) of 787 potential drug interactions emerged from new prescriptions. The alert systems produced 656 alerts of which 146 were irrelevant because of multiple alerting of the same interaction or of drug combinations currently no longer taken. Of the 510 remaining relevant drug-interaction alerts, 289 (56 x 7%) were overridden by community pharmacists without any action taken. If the pharmacist took care of a patient's prescription him- or herself (as opposed to just controlling a prescription after a technician took care of the patient), fewer drug-interaction alerts were overridden by the pharmacist [Odds ratio (OR) 0 x 6, 95% confidence interval (CI) 0 x 42-0 x 98; P=0 x 042). Technical overrides (by default settings) and pharmacists' overrides together accounted for 71 x 9% (566 of 787 potential drug interactions). Of the remaining 211 interactions alerts, 87 (41 x 2%) were checked more closely by consulting the literature, contacting the prescribing physician or discussion with the patient. This led to 55 (63 x 2%) interventions (close monitoring, adjustment of dose or ingestion time, therapy stop or switching to alternative therapy). Determinants associated with action taken after an interaction alert were potential high severity (severe or moderate) (OR 3 x 34, 95% CI 1 x 77-6 x 31; P<0 x 001) and alert flagged for the first time (OR 3 x 76, 95% CI 1 x 98-7 x 14; P<0 x 001). All severe potential drug interactions (n=10) generated an alert and all caused an intervention.
Pharmacists override a substantial proportion of drug-interaction alerts of minor or moderate potential severity by ignoring them or by programming the system to only flag drug interactions of potentially high severity. More sophisticated systems with improved sensitivity and specificity are required. Until these become available, it is important to ensure that at least potentially severe drug interactions are not missed; a goal that seems to be largely achieved.
药物相互作用警报系统常用于社区药房，以识别潜在的药物相互作用。然而，根据软件默认设置，药剂师可能会忽略过多的警报。我们对瑞士社区药房处理药物相互作用警报的情况进行了探究。
15名经过培训的药学专业学生在15家瑞士社区药房收集数据。评估了600名处方中使用≥2种药物的患者的用药史和药物相互作用警报，并就负责药剂师对药物相互作用警报的管理情况进行了访谈。
在所研究的15家药房中，计算机系统被设置为仅标记4家药房中的“严重”药物相互作用、6家药房中的“严重或中度”药物相互作用或5家药房中的“严重、中度或轻度”药物相互作用。药物相互作用警报的中位数频率随着默认严重程度的降低而增加，分别从每40次患者就诊和药房0.5次增加到40次，再到76次。由于这些默认设置，计算机系统忽略了新处方或重复处方上787条潜在药物相互作用警报中的277条（35.2%）。787条潜在药物相互作用中只有256条（32.5%）来自新处方。警报系统发出了656条警报，其中146条因对同一相互作用或当前不再服用的药物组合多次发出警报而无关。在剩下的510条相关药物相互作用警报中，289条（56.7%）被社区药剂师忽略且未采取任何行动。如果药剂师亲自处理患者的处方（而不是在技术人员处理患者后仅审核处方），药剂师忽略的药物相互作用警报较少[比值比（OR）0.6，95%置信区间（CI）0.42 - 0.98；P = 0.042]。技术忽略（通过默认设置）和药剂师的忽略共同占787条潜在药物相互作用的71.9%（566条）。在剩下的211条相互作用警报中，87条（41.2%）通过查阅文献、联系开处方医生或与患者讨论进行了更仔细的检查。这导致了55条（63.2%）干预措施（密切监测、调整剂量或服药时间、停药或改用替代疗法）。与相互作用警报后采取行动相关的决定因素是潜在的高严重程度（严重或中度）（OR 3.34，95% CI 1.77 - 6.31；P < 0.001）和首次标记的警报（OR 3.76，95% CI l.98 - 7.14；P < 0.001）。所有严重的潜在药物相互作用（n = 10）都产生了警报，并且都导致了干预措施。
药剂师通过忽略或设置系统仅标记潜在高严重程度的药物相互作用，忽略了很大一部分轻度或中度潜在严重程度的药物相互作用警报。需要更复杂、灵敏度和特异性更高的系统。在这些系统可用之前，重要的是要确保至少不遗漏潜在严重的药物相互作用；这一目标似乎在很大程度上已经实现。
