Potential Drug-disease Interactions Research Articles

Drug-drug and drug-disease interactions in the ED: Analysis of a high-risk population

A study was undertaken to determine the potential for adverse drug interactions (ADIs) and drug-disease interactions (DDIs) in a high-risk population of emergency department (ED) patients and to characterize drug-drug and drug-disease interactions in terms of percentage of patients at risk from existing drug regimens, percentage of patients at risk from ED treatment, relation between number of drugs and potential for interactions, types of drugs and diseases posing greatest potential for interaction, and the differences in a general versus community hospital population with respect to these parameters. Records of 205 consecutive patients, 111 from a general hospital teaching facility ED (Facility 1) and 94 from a community hospital ED (Facility 2) were retrospectively reviewed. The records of all patients receiving three or more medications and all patients older than 50 years of age receiving two or more medications were analyzed by two computer programs for the presence of potential drug-drug and drug-disease interactions. A total of 226 potential ADIs were found in 89 patients (47%), with 50% of ADIs being related to ED treatment. A total of 94 potential DDIs were found in 44 patients (21%), with 34% of DDIs being related to ED treatment. The risk of an ADI rose from 13% for patients taking 2 medications to 82% for patients taking 7 or more medications. Eleven medications and four disease categories were identified as having particular potential for interactions. No significant differences were found between the general and the community hospital populations in these respects. ED patients taking three or more medications and patients older than 50 years of age taking two or more medications are at substantial risk for adverse drug-drug and drug-disease interactions. The risk is increased in patients taking particular drugs or having particular disease states.

Use of computer drug-drug interaction program for detection of adverse drug reactions and related therapeutic problems.

Pharmacies currently using computers to detect drug-drug interactions may not be fully utilizing the computers' programs. Potential drug-disease interactions and some potential adverse drug reactions not traditionally defined as interactions can be detected by extending the basic concept of cross-referencing. For example, certain clinically important ADRs are readily detected by cross-referencing drugs which are often used to treat the results of specific ADRs with certain causative agents. The potential therapeutic implications of such a system when restricted to clinically significant ADRs can be readily appreciated, especially in situations where the pharmacist's time in patient-care areas is limited. This concept is currently being practiced at Bayfront Medical Center, and has added a new dimension to the clinical services provided by the pharmacy. It seems likely that detection of therapeutic situations in this manner may be appropriate in other hospital settings.

Computer support of pharmaceutical services for ambulatory patients

A prototype computerized pharmaceutical services support system (CPSSS) is described. CPSSS maintains records on approximately 40,000 patients; 1,300 outpatient prescriptions are dispensed per day. Using Univac hardware and software developed inhouse, CPSSS provides an online drug therapy profile. The prescription label, including auxiliary information, storage and stability guidelines as well as the traditional information, is automatically generated. Prior to medication dispensing, all information is verified by a pharmacist after the computer searches the patient medication profile for 5,400 potential drug-drug, 1,500 drug-disease state, over 100 drug-allergy and 200 drug-laboratory test interactions as well as identifying duplicate pharmacological therapy. Retrospectively, the patient population is described as to sex, age and number of diagnoses. The number of prescriptions per physician also is reported. Twenty drugs represent one-half of the total prescriptions, with 32% of patients taking diuretics and 30% taking tranquilizers. All new prescriptions were prospectively reviewed. Approximately 2% had potential interactions or pharmacological duplication of therapy problems. Approximately 30% of all new prescriptions duplicated exactly an active prescription on file. When a pharmacist initiated physician contact as a result of CPSSS and profile review, physicians changed therapy approximately 73% of the time when informed of duplicate therapy, 27% of the time when informed of potential drug-disease state interactions and 32% of the time when informed of potential drug-drug interactions.