Medication Reconciliation: How Pharmacist-Led Review Reduces Errors and Improves Patient Safety at Every Transition of Care

Medication reconciliation is a formal, standardized process of establishing an accurate list of a patient's current medications and comparing it with those being ordered at transition points in care to prevent errors.

Medication errors are identified in up to 67% of patients upon hospital admission and roughly 36% at discharge. These errors are common during transitions of care, and pharmacist-led medication reconciliation is critical to correcting these errors before they reach the patient.^1,2

Identifying Common Medication Errors

Patients are often prescribed new medications or have changes made to their existing regimen during transitions of care—such as hospital admission, changing units during hospital stays, or after discharge. These errors can occur in many ways.

Most medication history errors are omissions: an important piece of information is missing. These typically manifest in 1 of 3 ways: The first is a forgotten medication, when a patient fails to account for a certain medication. The second is a missing detail: A drug is recorded, but lacks important information such as its strength or frequency. The third, and most common, is the invisible route, in which medications not taken orally, such as transdermal patches, inhalers, injections, and eye drops, are omitted. The dangers associated with errors of omission can be significant and include therapeutic failure, withdrawal symptoms, and diagnostic confusion.

A duplication error occurs when a single medication is recorded multiple times or when 2 or more drugs from the same therapeutic class are prescribed without clinical intent. These can occur due to brand vs generic confusion, when both the brand and the generic are entered into the computer system. They can also occur through therapeutic duplication, when the patient is prescribed 2 different drugs that do the same thing.³ The dangers associated with a duplication error can include direct toxicity and overdose, severe adverse drug reactions, and fragmented clinical decisions, such as inaccurate diagnoses or masked lab results.

Dosing and frequency errors often appear to be correct on a chart but can be fundamentally mismatched with the patient’s clinical history. These errors often stem from systemic or communication errors. Transcription or copy forward errors can occur when the wrong dose is selected from a drop-down menu or when an outdated dose from a previous admission is copied forward. These can also occur with confusing units of measure, such as using milligrams instead of micrograms. Additionally, frequency misinterpretation may occur when there are ambiguous directions (eg, “take as directed”). The dangers associated with dosing and frequency errors can include toxicity and organ failure from overdose, accumulation toxicity from incorrect frequency, and timing misalignment when medications should be taken with or without food or at certain times during the circadian rhythm to work optimally.

During the chaos of transitions of care, potential drug interactions can be overlooked. This often occurs when patients fail to report OTC supplements because they don’t view them as medications. Some supplements can cause severe drug interactions (eg, St John’s wort can decrease the effectiveness of anticoagulants and antirejection medications). A drug that is safe and effective for a patient at home may become toxic when combined with new hospital therapies.⁴ These drug interactions can reduce therapeutic efficacy, result in toxicity (eg, organ damage, respiratory depression, or internal bleeding), and alter cardiac rhythms (QT prolongation).⁵

The Reconciliation Process

On the surface, medication reconciliation may look like a simple process. In practice, however, medication reconciliation is one of the most complex and error-prone processes in health care due to its reliance on human memory, fragmented data, and continuous transitions of care.⁶

First, develop a list of current medications. Creating the best possible medication history starts with the pharmacist or trained technician conducting a patient interview to identify all medications the patient has been taking. This interview should use open-ended questions about all prescribed medications, OTC medications, supplements, vaccinations, and recreational substances.

Once the interview is completed, pharmacists should verify the information with at least one other source, where possible. This may include community pharmacy records, pill bottles, and previous discharge summaries.⁷ When compiling this list, it is important to capture complete details by recording the name, strength, route, frequency, and indication for each item.

Next, develop a list of prescribed medications by reviewing the new orders intended for the patient’s current treatment plan. During this step, practitioners review all available health history information and determine which medications should be continued, modified, or discontinued.

Compare both lists. Identify any unintended differences between what the patient was taking and what is now ordered. This step bridges the gap between medication history and newly prescribed orders.

Finally, make clinical adjustments and communicate the final list. Resolve discrepancies by adjusting doses, restarting omitted medications, or discontinuing duplicates, and provide the updated, reconciled list to the patient, caregivers, and subsequent health care providers.

Medication reconciliation should occur at every transition, including admission, intrafacility transfer, and discharge.²

Impact on Patient Outcomes

Medication reconciliation serves as a critical safety net, enhancing patient outcomes during transitions of care. A primary benefit of medication reconciliation is preventing errors such as omissions, duplications, and dosing errors. When performed appropriately, medication reconciliation can reduce discrepancies from as high as 70% to as low as 15%.⁸

Effective reconciliation can also reduce 30-day hospital readmissions by up to 50%.⁹ By catching discrepancies such as omissions and unintended dosing errors, providers can prevent many of the adverse drug reactions that force patients back into the hospital.

The interview process also allows the identification of barriers to adherence and provides an ideal opportunity to educate patients about their new medication regimens, increasing the likelihood of adherence.

Clinical Takeaways

Medication reconciliation systematically bridges the gaps that occur during transitions of care by reducing medication errors such as omissions, duplications, dosing errors, and drug interactions. When a comprehensive, accurate, and unified medication list is created and prioritized, hospital efficiency and patient safety are improved, costly readmissions are reduced, and a safe and effective path to recovery is achieved.

About the Author

Kathleen Kenny, PharmD, RPh, earned her PharmD degree from the University of Colorado Anschutz. She has more than 30 years of experience as a community pharmacist and works as a clinical medical writer based in Albuquerque, New Mexico.

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