Medication errors remain one of the most common causes of unintended harm to patients. They contribute to adverse events that compromise patient safety and result in a large financial burden to the health service. The prevention of medication errors, which can happen at every stage of the medication preparation and distribution process, is essential to maintain a safe healthcare system. One third of the errors that harm patients occur during the nurse administration phase: administering medication to patients is therefore a high-risk activity. This article highlights factors that contribute to medication errors, including the safety culture of institutions. It also discusses factors that relate specifically to nurses, such as patient acuity and nursing workload, the distractions and interruptions that can occur during medication administration, the complexity of some medication calculations and administration methods, and the failure of nurses to adhere to policies or guidelines.