OBJECTIVES: To describe the pharmacological characteristics of medicines involved in administration errors and determine the frequency of errors with potentially dangerous medicines and low therapeutic index, in clinical units of five teaching hospitals, in Brazil. METHODS: Multicentric study, descriptive and exploratory, using the non-participant observation technique (during the administration of 4958 doses of medicines) and the anatomical therapeutic chemical classification (ATC). RESULTS: Of that total, 1500 administration errors were identified (30.3%). The administration of pharmacological groups - ATC (cardiovascular system, nervous system, alimentary tract and metabolism system and anti-infectives for systemic use) showed a higher frequency of errors. In 13.0% of errors were involved potentially dangerous medicines and in 12.2% medicines with low therapeutic index. CONCLUSION: The knowledge of the pharmacological profile could be an important strategy to be used in the prevention medication errors in health institutions.
Medication errors; Medication systems hospital