Safe medication administration is a vital component of the nursing role. Every day, nurses make critical decisions regarding the safety, appropriateness, and effectiveness of the medications administered to their clients. Examples of decisions that a nurse might make during client care are as follows:

• Is my client’s heart rate within the correct range to receive this beta-blocker medication?
• Does my client have adequate renal function prior to administering this dose of antibiotic?
• Is this pain medication effective in controlling my client’s discomfort?

To make safe decisions regarding medication administration, the nurse must have a strong understanding of pharmacology, the science dealing with actions of drugs on the body. Symptom management and a client’s overall well-being are strongly connected to the appropriate administration of medications prescribed in a client’s treatment plan. Before a student nurse reviews a medication order, checks a medication administration record, or removes a medication from a dispensing machine, it is essential to have a foundational understanding of how medications interact with the human body. This chapter will review basic concepts related to pharmacokinetics and pharmacodynamics.