The perioperative period is a dynamic and risky time for patients. After complications related directly to the surgery itself, medication complications are the next most common adverse events in hospitalized patients [1]. This chapter will address patient safety related to medication practices around surgery, excluding anesthesia and intraoperative medication use. A discussion of general principles will be followed by a focus on the more common complications and high-risk medication groups.

Medication history and reconciliation

Recording a full and accurate medication list is an essential part of a thorough patient history, yet doing so presents a time-consuming challenge in a patient on multiple medications. Reasons for the challenge include the plethora of medications that have been developed and marketed in the last decades that may be unfamiliar to the physician, the difficulty for the patient to remember the full medication list and details of use, and the immature state of electronic health information that does not yet allow universal sharing of data about patients' medical history between multiple health information platforms. As a result, a significant proportion of patients in hospital have incomplete or inaccurate medication histories.