Background: Interruptions have been reported to contribute to clinical errors and procedural failures. Objective: To analyze the interruptions experienced by nurses during the preparation and administration of high-risk medications. Methodology: A cross-sectional study was conducted in an intensive care and inpatient unit. The interruptions experienced by nurses during the medication process were observed through two checklists. The sample was selected by convenience in April-May 2019. Descriptive statistics was used to analyze quantitative data in IBM SPSS Statistics software, version 24.0, while content analysis was used to analyze qualitative data. Results: In 193 medication processes, there were 137 interruptions. Other members of the healthcare team initiated most interruptions through conversations. These interruptions were mostly negative and occurred during the preparation phase. The multitasking strategy was used to manage them. Conclusion: Interruptions during the medication process were primarily associated with professional and social communications. The impact of these interruptions varied depending on the phase of the process.