Nursing care
Medication Reconciliation: the method, the errors, and the exam
Written and reviewed by Dana Whitfield, RN, MSN · 5 min read · Updated September 2026
Short answer
Medication reconciliation is the process of comparing a patient's current medications against every new order at each transition of care, to catch omissions, duplications, and dosing errors before they reach the patient. It happens on admission, transfer, and discharge. The medications most often missed are the ones patients don't think to mention: over-the-counter drugs and eye drops.
What the skill is for
Every handoff between care settings — admission, transfer between units, discharge home — is a point where a medication list can silently change. A drug gets dropped because it wasn't on the transfer paperwork, a dose gets duplicated because the admitting team didn't know the patient was already on it, or a home medication gets missed entirely because nobody asked the right question. Reconciliation exists to catch these before the next dose is given.
The skill is not the same as a medication history. A history is a one-time collection of what the patient takes; reconciliation is the ongoing comparison of that list against every new set of orders, repeated at every transition for the length of the stay. A patient can have an accurate history taken on admission and still receive a duplicated or omitted drug at discharge if reconciliation isn't repeated at that second transition.
The method, step by step
Start by building the most accurate possible list of what the patient was taking immediately before this transition — prescription drugs, dose, route, and frequency, sourced from the patient, family, pharmacy records, or a prior facility, not from memory or an outdated chart entry. Then compare that list line by line against the new orders written for this stage of care.
For every mismatch, ask why: is the drug intentionally being held, has the dose changed for a clinical reason, or was it simply left off? Resolve each discrepancy with the prescriber before it becomes an administered dose, not after. The step patients and even staff underestimate is asking specifically about over-the-counter drugs, supplements, and eye drops — these are the categories patients consistently leave off when asked the general question 'what medications are you taking?' because they don't count them as medications.
Where it goes wrong
The most common failure is an incomplete source list, not a comparison error. If the initial list is wrong, every step after it inherits that error. This is why the omissions cluster around the same categories at every transition: over-the-counter analgesics, laxatives, vitamins, and eye drops for glaucoma or dry eye. Patients answer 'what medications do you take' with their prescription list and stop there.
The second common failure is treating reconciliation as a one-time admission task rather than repeating it at every transition. A medication list reconciled correctly on admission can still fail at discharge if nobody reconciles again against the discharge orders, particularly when a patient has moved between units and each handoff introduced a small, uncaught change.
Practising it deliberately
Build the habit of asking about medication categories rather than asking one open-ended question. Ask specifically about eye drops, ear drops, inhalers, topical creams, herbal supplements, and anything taken 'as needed' — patients mentally file these differently from their regular tablets and will not volunteer them unprompted.
Practise reconciling against a real or simulated discharge summary rather than only at admission, since the discharge transition is where dropped medications most often reach the patient without another safety check behind them. Work through case scenarios where the home list and the new orders disagree, and practise the specific move of contacting the prescriber to resolve the discrepancy rather than guessing which list is correct.
Applying it on the exam
Exam items testing this skill usually present a medication list from one setting and a new order set from another, then ask which action the nurse should take first. The correct answer is almost always to identify the discrepancy and clarify with the prescriber, not to administer either list as written and not to assume the newer list is automatically correct.
Watch for items where the discrepancy is an omission rather than an addition — a home medication simply absent from the new orders, with no explanation given. These are testing whether you notice what is missing, which is harder to spot than a duplication or an obvious dosing error. If a scenario mentions over-the-counter drugs or eye drops at all, treat that as a deliberate signal that the item is testing whether you would have asked about them in the first place.
A worked example
A patient is being discharged home after a hip replacement. Their home medication list, taken on admission, included daily aspirin, a statin, and latanoprost eye drops for glaucoma. The discharge order set includes a new anticoagulant, the statin, and an analgesic — but no mention of the eye drops or the aspirin.
Reconciliation requires flagging both omissions before the patient leaves. The aspirin needs a clinical decision: is it intentionally held because of the new anticoagulant, or was it simply left off the transcription? The eye drops need the same scrutiny for a different reason — they carry no interaction risk with the surgical care, so their absence is very likely an oversight from a list nobody asked about specifically. Both go back to the prescriber for confirmation before the discharge paperwork is finalised, which is the reconciliation step doing exactly the job it exists to do.
The next step on this is the same as on everything else here: answer questions and read the rationales. Our pharmacology practice questions are the closest set to what this page covers.
One question from the pharmacology set
A client with heart failure is started on furosemide 40 mg PO daily. Which findings should the nurse report to the provider before administering the next dose? Select all that apply.
Rationale
Furosemide is a loop diuretic, so the two things you are watching are potassium and kidney function. A potassium of 2.9 mEq/L is below the 3.5–5.0 reference range and puts the client at risk for dysrhythmia — hold and report. Muscle cramps with palpitations are the clinical face of that same hypokalemia, so they are reported together, not separately. A creatinine that doubles signals the diuresis has outrun renal perfusion. A blood pressure of 132/78 and a 1 kg loss are the expected response to the drug working, not reasons to hold it.
Answer: A, D, E
Common questions
When should medication reconciliation be performed?
At every transition of care: admission, any transfer between units or facilities, and discharge. It is not a one-time admission task — a list reconciled correctly on admission can still fail if it isn't reconciled again at the next transition.
What medications do patients most often forget to mention?
Over-the-counter drugs, supplements, and eye drops. Patients tend to answer a general question about medications with their prescription list only, because they don't mentally categorise these as medications.
What should a nurse do when the home medication list and new orders don't match?
Flag the discrepancy and clarify with the prescriber before administering either version. Do not assume the newer order set is automatically correct, and do not guess at the reason for the mismatch.
How is medication reconciliation different from a medication history?
A medication history is a one-time collection of what a patient is taking. Reconciliation is the repeated comparison of that list against new orders at every subsequent transition, which is what catches errors introduced after the initial history was taken.
How do NCLEX-style questions usually test medication reconciliation?
By presenting two lists that disagree — often an omission rather than an obvious duplication — and asking for the nurse's first action. The expected answer is to identify the discrepancy and contact the prescriber, not to administer either list as written.
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