Drug interactions from HIV therapies continue to increase as new drugs are approved and antiretroviral agent regimens become more complex. Drug interactions are associated with substantial risk of adverse pharmacokinetic or pharmacodynamic interactions, resulting in decreased therapeutic efficacy, increased incidence of drug toxicities, and subsequent emergence of drug resistance. Therefore, the identification, resolution, and prevention of drug-related problems are important determinants for patient clinical management. The proposed study investigates the prevalence (cross-sectional study part) of drug-drug interactions within the Swiss HIV Cohort Study patients using the University of Liverpool drug interaction database (www.hiv-druginteractions.org). This study further includes an intervention part, which informs the physician of clinically significant drug-drug interactions by using this database. A second survey will determine if the occurrence of potential drug-drug interactions is reduced for physicians who used the database.
