5.1 Math Calculations Introduction

Medication errors remain a significant concern in healthcare settings. In 2023, medication errors accounted for 14.1% of all serious patient safety events reported to the nation’s largest event reporting database, marking an increase from 13.2% in 2022 . These errors can occur at various stages of the medication process, including prescribing, transcribing, dispensing, and administration. Nurses play a critical role in the final step of medication administration, bearing the responsibility to ensure the medication is safe for the patient. To safely prepare and administer medications, nurses perform a variety of mathematical calculations, such as determining the number of tablets, calculating the amount of solution, and setting the rate of an intravenous infusion.^[1]

Dosage calculation in clinical practice is more than just solving a math problem. Nurses must perform several tasks during drug calculations, such as reading drug labels for pertinent information, determining what information is needed to set up the math calculation, performing the math calculations, and then critically evaluating the answer to determine if it is within a safe dosage range for that specific patient. Finally, the nurse selects an appropriate measurement device to accurately measure the calculated dose or set the rate of administration.^[2] This chapter will explain how to perform these tasks related to dosage calculations using authentic problems that a nurse commonly encounters in practice.