Recognition and management of potential drug–drug interactions in patients on internal medicine wards

Abstract

Introduction Our aim was to study and possibly improve the clinical management of potential drug-drug interactions (pDDIs) in hospitalized patients by specific interventions. Methods During the initial period, inpatients on three medical wards were screened for major and moderate pDDIs using the interaction screening program Pharmavista. During the second period, patients at discharge were screened similarly. After assessment of the detected pDDIs for clinical relevance, written recommendations and/or information about the pDDIs were sent to the treating physicians. Feedback from the physicians and implementation of the recommendations were analyzed. Results During the initial period, 502 inpatients were exposed to 567 pDDIs, of which 419 (74%) were judged to be clinically relevant. Three hundred and forty-nine substantiated recommendations and 70 simple information leaflets were handed out to the physicians. Eighty percent (278 of 349) of the recommendations were accepted and implemented. During the second period, 792 patients at hospital discharge were exposed to 392 pDDIs, of which 258 (66%) were judged to be clinically relevant. Two hundred and forty-seven substantiated recommendations and 11 simple information leaflets were sent to the physicians. Seventy-three percent (180 of 247) of the recommendations were accepted. At hospital discharge, 47 of 71 interventions recommending checkable medication changes were implemented. One year after hospital discharge, 11 of 13 checked medication changes were still in place. Conclusions Clinically relevant pDDIs are common in patients on medical wards, and their management can be influenced by providing substantiated recommendations to physicians. Most changes in medication following such recommendations are still in place 1 year after discharge.

Potential drug–drug interactions and radiodiagnostic procedures: an in-hospital survey

“…The number of drugs, co-morbidity, and advanced age has already been indicated by other studies as independent predictors of potential DDI occurrence [7,9,13,19]. In our sample, female patients, showed a borderline OR [1.4 (0.9-1.6)], almost significant, when compared with males.…”

“…This tool was designed to assist healthcare providers in identifying possible interactions among a series of co-administered medications and it has proven to be even more sensitive in predicting potential DDIs than expert physicians [12][13][14][15]. Following the software directives, each interaction was categorized as 'major', 'moderate' or 'minor', in light of the severity of the resulting ADR.…”

Drug-drug interactions and risk of bleeding among inpatients on warfarin therapy: a prospective observational study

“…In the developed world (Europe and USA) anticouglation therapy is commonly used for elderly patients [3,9,19,21]. In contrast, in this study above half of the subjects on warfarin were in the age less than forty.…”

“…About half of these interactions were clinically significant resulting in change in INR and/or bleeding. Parallel to this study, an interventional study on recognition and management of drug – drug interactions in inpatients at the Cantonal Hospital of Baden, found 567 DDIs in 502 inpatients, of which 419 (74%) were judged to be clinically relevant [19]. Likewise, the prevalence of DDIs in outpatients was reported as high as 84% [20,21].…”

Prevalence of potential drug–drug interactions in bone marrow transplant patients

“…Clinical pharmacists have the necessary expertise to contribute to all aspects of the drug utilization process, and possess in-depth understanding of the clinical relevance of DDI and adverse drug events. The decision support system is another effective strategy to help identify DDIs, but the software program that selects drug interactions should have high sensitivity to detect interactions of clinical significance, and high specificity to ignore clinically insignificant interactions [8,18,[23][24][25][26][27][28].…”