RESUMEN
Objective: To evaluate errors in dental prescriptions of antibiotics for therapeutic purpose. Material and Methods: This was a descriptive study using a random and calculated sample of 366 prescriptions (July1 2011 to June 30 2012), from a total of 31 105 dental prescriptions, was surveyed in an important drugstore chain in a large Brazilian city. Data was validated by double entry in Epi-data (EpiData Assoc, Odense M, Denmark) and then analysed in SPSS (version 19.0, Chicago, IL, USA). Statistical analyses included the calculation of proportions with a 95% confidence interval (CI). Results: We identified 272 prescriptions for therapeutic purpose. Prescription errors involved spelling of the antibiotic name, dose, dosing intervals and duration of treatment. A total of 116 prescriptions (42.6%; 95% CI 36.9%-48.6%) were considered to be totally correct with regard to the generic name, dose, dosing interval and duration of the antibiotic therapy. Most of the antibiotics prescribed by dentists showed errors related to the name, dose, intervals and duration of treatment. Conclusion: These errors may compromise the effectiveness of drug therapy, contribute to microbial resistance and increase the risk of adverse events and costs of treatment.