Prevalence of drug-drug interactions at hospital entry and during hospital stay of patients in internal medicine.

OBJECTIVE: The aim of this study was to assess potential drug-drug interactions (pDDIs) at hospital admission, during hospitalization and at discharge and to evaluate the number of pDDIs created during hospitalization. METHODS: The medication of 851 patients was screened for pDDIs (major and moderate severity) using the screening program Pharmavista. The frequency of pDDIs per patient, per number of drugs and drug pairs was estimated. RESULTS: During hospitalization, the frequency of major and moderate pDDIs per patient was 1.11, which was higher compared to hospital admission (0.59) or to hospital discharge (0.60). The frequency of major and moderate pDDIs per drug prescribed (13.7% vs. 9.1%) or per drug pairs analyzed (4.5% vs. 2.3%) was higher at hospital admission compared to hospital discharge. 47% of all major and moderate pDDIs at discharge were due to a medication change during hospitalization. CONCLUSIONS: Although the number of major and moderate pDDIs per patient did not increase from hospital admission to discharge, it is important to realize that 47% of all major and moderate DDIs at hospital discharge were created during hospitalization. Prescribing drugs with a low risk for pDDIs as well as careful monitoring for adverse drug reactions are important measures to minimize harm associated with DDIs.

Evaluation of frequently used drug interaction screening programs.

OBJECTIVE: Drug-drug interaction (DDI) screening programs are an important tool to check prescriptions of multiple drugs. The objective of the current study was to critically appraise several DDI screening programs. METHODS: A DDI screening program had to fulfil minimal requirements (information on effect, severity rating, clinical management, mechanism and literature) to be included into the final evaluation. The 100 most frequently used drugs in the State Hospital of Baden, Switzerland, were used to test the comprehensiveness of the programs. Qualitative criteria were used for the assessment of the DDI monographs. In a precision analysis, 30 drugs with and 30 drugs without DDIs of clinical importance were tested. In addition, 16 medical patient profiles were checked for DDIs, using Stockley's Drug Interactions as a reference. MAIN OUTCOME MEASURE: Suitability of DDI screening program (quality of monographs, comprehensiveness of drug list, statistical evaluation). RESULTS: Out of nine programs included, the following four fulfilled the above mentioned criteria: Drug Interaction Facts, Drug-Reax, Lexi-Interact and Pharmavista. Drug Interaction Facts contained the smallest number of drugs and was therefore the least qualified program. Lexi-Interact condenses many DDIs into one group, resulting in less specific information. Pharmavista and Drug-Reax offer excellent DDI monographs. In the precision analysis, Lexi-Interact showed the best sensitivity (1.00), followed by Drug-Reax and Pharmavista (0.83 each) and Drug Interaction Facts (0.63). The analysis of patient profiles revealed that out of 157 DDIs found by all programs, only 18 (11%) were detected by all of them. No program found more than 50% of the total number of DDIs. A further evaluation using Stockley's Drug interactions as the gold standard revealed that Pharmavista achieved a sensitivity of 0.86 (vs Drug Interaction Facts, Lexi-Interact and Drug-Reax with a sensitivity of 0.71 each) and a positive predictive value of 0.67. CONCLUSION: None of the four DDI screening programs tested is ideal, every program has its strengths and weaknesses, which are important to know. Pharmavista offers the highest sensitivity of the programs evaluated with a specificity and positive predictive value in an acceptable range.

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

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.

The use of an hydrogen peroxide multipurpose isolator for inhouse preparation of human embryo culture media: a unique successful Swiss randomized prospective study.

PURPOSE: To develop inhouse made (IHM) embryo culture medium with a Multipurpose Isolator and compare the embryo development in a prospective randomized study with commercial media. METHODS: Fertilization by intracytoplasmic single sperm injection (ICSI) of Metaphase II oocytes obtained after 96 controlled ovarian hyperstimulation cycles in patients not older than 37 years. Transfer of zygotes to IHM or commercial Cook Sydney IVF Cleavage medium (SIC) immediately after pronucleus observation. Evaluation of embryo cleavage and score, pregnancy, and implantation rate. RESULTS: From 100 zygotes cultured in SIC, 61% were at the 4 cell stage 45 h after ICSI compared to 77% (78/101) in the IHM, P < 0.05. The mean embryo score with IHM was 3.9 +/- 0.9 compared to 3.5 +/- 1.2 with SIC, P < 0.05. The clinical pregnancy rate per transfer was 38.9% (37/95), the implantation rate was 23% (46/200), and no differences were observed between the groups.