The related primer on medication error, adverse drug events occur when exposure to a medication results in harm. Correct medication use occurs when the “five rights” are followed, meaning the right dose of the right medication is administered to the right patient, at the right time, and by the right route. However, this simple phrase obscures the fact that the five rights must be individualized, as they are affected by the patient’s age, medical condition, physiologic status, and other factors such as allergies. While pharmacists’ contribution to medication safety has been historically focused on dispensing, pharmacists’ roles have expanded as medication therapy has increased in complexity, and many patients—even those with serious illness—can now receive care in the home and in community settings.
Pharmacists also have a crucial system-level role in planning and leading medication safety programs and improvement initiatives within health care organizations. These initiatives may include developing risk-specific protocols for high-alert medications; identifying and evaluating high-risk processes (e.g., total parenteral nutrition, compounding, pediatric dose preparation) that require special attention, protocols, and training; evaluating medication error data; evaluating and implementing new medication technologies; and fostering robust error reporting processes. Clinical trials are another area in which pharmacist leadership in designing safe protocols is critical, as there are fewer standardized safeguards in place to ensure correct medications and doses are delivered to patients.
Pharmacists have a central role in ensuring medication safety across the continuum of care. The complexity of the medication prescribing and delivery processes can make it difficult to prove the beneficial effect of pharmacists on adverse outcomes directly, but pharmacist involvement has been shown to reduce errors, improve prescribing practices, and enhance patient monitoring across settings. For example, a cluster-randomized trial of pharmacist involvement in medication management planning on hospital admission showed a dramatic reduction in medication errors within the first 24 hours of hospitalization. A meta-analysis of 13 studies of pharmacist interventions at transitions of care estimated a 37% reduction in medication errors and a decrease in emergency department visits after hospital discharge. A recent randomized controlled trial of a pharmacist-led intervention in primary care practices in the United Kingdom tested an intervention bundle comprised of review of electronic medical records, prescriber feedback, education on error reduction, and support for improving local safety systems. This bundle of practices resulted in significant increases in appropriate prescribing and monitoring practices for specific error-prone situations, such as elderly patients taking loop diuretics or angiotensin-converting enzyme inhibitors. Despite these generally positive results, many health systems have found it difficult to hire enough qualified pharmacists, either because of a shortage in the available pharmacists or the costs of implementation. Given the latter factor, further studies that consider the return-on-investment of pharmacist-led safety programs should be considered.