[Potential drug interactions in adults and the elderly in primary health care]

The objective of the present study was to characterize the potential drug interactions (PDI), estimating the factors associated to their occurrence in adults and the elderly assisted by the Programa Médico de Família de Niterói, Rio de Janeiro. This is a sub-study of STUDY DIGITALIS, which included individuals enrolled in the Niteroi Family Medical Program (45-99 years). In this study, 341 individuals with a prescription of two or more drugs were analyzed. The classification of PDI followed MICROMEDEX. There were 113 different interactions. Of the total number of individuals, 63.6% had at least one PDI. The variables with higher probability of PDI were: lower level of schooling; income less than R$800.00; absence of health plan; previous diagnosis of hypertension and diabetes; use of 5 or more medications prescribed. After adjustment, the variables previous diagnosis of hypertension and diabetes and use of 5 or more prescription drugs remained statistically significant. Careful management of primary care treatment with monitoring is important in patients with PDI, especially in patients who are more susceptible.