FONTES DE INFORMAÇÕES SOBRE INTERAÇÕES MEDICAMENTOSAS: HÁ CONCORDÂNCIA ENTRE ELAS?

Introduction. The reliable and correct information about drugs is an essential step to promote the rational use of drugs, particularly drugs with a high number of interactions such as warfarin. Objective. To correlate five information sources about drug interactions using warfarin as an instrument of comparison. Casuistic and Methods. It is a descriptive study. It was selected five information sources about drug interactions: Micromedex®, World Health Organization Model Formulary 2008, "Guia Zanini-Oga de Interações medicamentosas", PR Vade Mécum®, Package insert of brand warfarin. The variables studied were: number of interactions, the presence of drug-food or drug-alcohol interactions or both, classification of the severity of interactions, number of interactions considered major, manner of interaction presentation (specific drug or pharmacologic group), and identification and classification according to the Anatomical Therapeutic Chemical (ATC) of drugs with potential interaction with warfarin. Results and Discussion. The number of interactions provided by the information sources ranged from 46 to 326, one source did not consider interaction with food or alcohol or both, only two sources classified according to severity of interactions, no drug was present simultaneously in all information sources. Nervous System drugs were the most prevalent drugs with potential interaction with warfarin. Conclusion. The information sources presented heterogeneous profiles in relation to interactions involving warfarin, emphasizing the discrepancy among amount, classification and presentation of drug interactions. [ABSTRACT FROM AUTHOR]