Medicines reconciliation: how to do it right, every time
Medicines reconciliation is the process of building the most accurate possible list of what a patient is actually taking, comparing it with what has been prescribed, and resolving every discrepancy before it becomes an error. It happens in hospital (admission, transfer, discharge) and in community pharmacy (Discharge Medicines Service, New Medicine Service, and every repeat prescription that comes across the counter). Done well, it is one of the highest-impact patient-safety activities in UK pharmacy. Done badly, it is behind a large share of the medication errors that end up on incident reports.
What is medicines reconciliation?
Medicines reconciliation (often called med rec) is a structured, verifiable process. You take at least two independent sources, you compare them line by line, and you document what has changed and why. It sits at the heart of medicines safety across both settings of UK pharmacy. In hospital, NICE guidance (NG5) expects reconciliation within 24 hours of adult admission. In community pharmacy, it happens whenever a prescription is dispensed, whenever a patient starts a new medicine, and whenever someone comes home from hospital and has to make sense of what has changed.
The role is now largely carried by pharmacy technicians in hospital, and increasingly by pharmacy technicians and pharmacists together in community. Pharmacy technicians take the history, cross-check the sources, spot the discrepancies, and hand a clean, evidenced list to the pharmacist for clinical decisions. Medicines reconciliation is one of the roles that has grown fastest for pharmacy technicians over the last decade. It is where technical judgement, communication skill and documentation all come together.
Where medicines reconciliation happens in hospital
In hospital, three settings matter most. Each has different pressures, different sources, and different failure modes.
Admission
Building the drug history within 24 hours of the patient arriving. The busiest setting and where most errors are caught.
Transfer
When the patient moves between wards, teams or care settings. Medicines started acutely can end up carried on for months if this step is skipped.
Discharge
Making sure the discharge letter and TTO match what the patient will actually take at home, with a clear rationale for every change.
Where medicines reconciliation happens in community pharmacy
Community pharmacy carries the other half of the load. Most patients never see a hospital pharmacist, but they see their community pharmacist every month. The reconciliation opportunities are quieter, but the volume is huge and the errors are the same. Missed doses, duplicated therapy, medicines the patient has quietly stopped, dose changes the surgery meant to make but didn’t send through cleanly.
Discharge Medicines Service (DMS)
NHS England’s DMS refers discharged patients to their community pharmacy 7–14 days after leaving hospital. The pharmacy team reconciles the discharge summary against the GP repeat, checks what the patient understands, and feeds discrepancies back to the surgery.
New Medicine Service (NMS)
When a patient starts a new medicine for a long-term condition (inhaler, DOAC, statin, antihypertensive, oral hypoglycaemic), two follow-up conversations at 7–14 and 14–21 days check they’re taking it, tolerating it, and understanding it.
Repeat prescriptions & care homes
Every repeat prescription is a reconciliation opportunity. Community teams spot dose changes the patient wasn’t told about, medicines that quietly disappeared, and MAR-chart mismatches in care home cycles before they reach the resident.
The sources you compare
Medicines reconciliation is only as good as the sources behind it. NICE and Royal Pharmaceutical Society guidance is clear: use at least two independent sources. Rely on one and you will miss things. The strongest combinations pair a patient-based source with a system-based source. The exact mix looks different in hospital and community pharmacy, so both settings are covered below.
Sources in hospital
Patient interview
The single richest source of information, and the one most often skipped when the ward is busy. Ask open questions first, then follow up with prompts about creams, inhalers, eye drops, injections, herbal remedies, and things bought from the pharmacy without a prescription.
“Talk me through everything you take, starting with tablets. Anything I might not think of?”GP summary care record or GP list
The formal prescribed list. Compare against the patient interview to find recent changes, dose adjustments and stopped medicines.
Check the date. A record printed three weeks ago will not reflect this week’s changes.Community pharmacy dispensing record
From a hospital perspective this is excellent for spotting compliance issues. If a monthly prescription has not been collected for two months, that medicine may not actually be taken any more. Call or fax the patient’s nominated community pharmacy for a copy.
Especially useful for controlled drugs, insulin, and drugs the patient may be reluctant to admit not taking.Patient’s own medicines (POM) brought in
The physical containers the patient brings from home. Check labels for dose, strength, frequency and pharmacy of dispensing. Cross-reference with the GP list.
Do not discard until reconciliation is complete. Modified-release brands and unusual formulations can be hard to work out otherwise.Family, carer or care home records
Vital for patients who cannot give a full history themselves. A care-home MAR chart is often the most reliable source for elderly patients with cognitive impairment.
Ask care homes to fax or email the current MAR chart if the patient does not arrive with one.Recent hospital discharge letter
Especially useful when the patient has been readmitted within a few weeks. Shows what was started or stopped last time, and any dose changes made in secondary care.
Discharge letters are also the most common source of unresolved discrepancies. Verify against the GP record.Sources in community pharmacy
When the reconciliation is being done IN community pharmacy, the sources shift. Your own PMR is useful historical context but it isn’t a current-state source — it only shows what has been dispensed at your pharmacy, not anything the patient has been prescribed since, nor anything they’ve stopped. The strongest current-state sources are the ones below.
Patient interview
Same principle. Open questions first, then follow up. In DMS this often happens in a private consultation area or by phone within 7–14 days of discharge. In NMS at first supply and again at the two follow-ups.
“Since you came out of hospital, what are you actually taking? Anything you’ve stopped or forgotten?”Hospital discharge summary (DMS)
Under the Discharge Medicines Service the hospital team refers the patient to you with a discharge letter. This is the reference document. Reconcile it against what the patient tells you they’re actually taking and against the GP repeat once the surgery has actioned it.
The gap between discharge and the surgery updating the record is where DMS interventions catch the most errors.GP surgery record / Summary Care Record
Where the Summary Care Record is accessible with consent, use it. Otherwise a phone call to the prescriber. Get in the habit of building relationships with prescribing clinicians at your linked practices — you get quicker answers when it matters.
Ask specifically about recent titration, brand switches and stopped medicines that might still appear on the repeat.Patient’s own medicines at home
Ask the patient (or family/carer) to bring in everything from the cabinet. Leftover stock from before admission. Old strengths of a titrated medicine. Anything they’ve bought over the counter. It’s often surprising what turns up.
Especially useful when a hospital changed an inhaler or a DOAC brand and the patient is still using both.Care home MAR chart
For care-home patients, the current MAR chart against the previous cycle and against the GP repeat. Look for prescription changes the surgery made but didn’t communicate cleanly, and any as-required medicines that have crept into regular use.
Where you supply the home, you’re also the safety net for MAR-chart transcription errors made at the surgery.Why medicines reconciliation matters
Errors caused by incomplete or inaccurate medication histories are among the most common preventable causes of harm in UK healthcare. National reporting data suggests medicines reconciliation errors are behind a significant share of adverse drug events at hospital admission and discharge, and they account for many of the interventions community pharmacists make on repeat prescriptions and DMS referrals.
The clinical consequences run from the mundane to the catastrophic. A missed dose of a beta-blocker can cause hypertensive rebound. An anticoagulant continued when it should have been paused can cause a bleed. An antidepressant stopped without tapering can trigger a discontinuation syndrome. A previously discontinued statin that is quietly re-prescribed can go on for years unnoticed.
Medicines reconciliation is also where much of your GPhC inspection evidence is built. Every reconciled list, every documented rationale for change, and every intervention logged is proof of the pharmacy team’s contribution to patient safety. A trust that can show consistent, well-documented reconciliation is a trust that can defend itself when an incident is investigated.
A worked example: 78-year-old admitted with a fall
To see what medicines reconciliation actually looks like, follow this admission through. Same patient, same paperwork, two different levels of rigour.
❌ Rushed reconciliation
Situation: 78-year-old woman, admitted after a fall at home. GP letter faxed. Ward is busy.
What happens: Pharmacy technician glances at the GP summary, transcribes it onto the drug chart, moves on. Patient not interviewed. Family not consulted. Bag of medicines from home left on the locker.
What gets missed: Patient had stopped her ramipril two months ago after a bad cough. She was taking regular co-codamol from her local pharmacy for hip pain (not on GP record). Her furosemide had been increased three weeks ago at a GP review that hadn’t updated the electronic record yet.
Result: patient prescribed her old ramipril dose, no analgesia plan, wrong furosemide dose. Fall could recur. Pain not managed.
✅ Proper reconciliation
What happens: Pharmacy technician takes 15 minutes at the bedside. Patient interview. GP summary print-out. Community pharmacy dispensing record confirmed by phone. Bag of medicines from home checked label by label.
Findings:
- Ramipril self-stopped 8 weeks ago due to cough → flag to pharmacist, may need alternative ACE-inhibitor or ARB
- Co-codamol purchased OTC, 8 tablets/day → document, review analgesic ladder, screen for constipation and drowsiness
- Furosemide dose increased 20 mg → 40 mg 3 weeks ago at GP surgery, not yet on SCR → update chart, prescribe increased dose
- Herbal ‘calm’ supplement bought in Boots → contains valerian → add to allergies/interactions screen
Result: accurate drug history, prescriber flagged to review, patient interviewed about analgesia preferences, hidden medicines exposed.
The difference between the two is not knowledge. It is process, time protected for the interview, and the discipline to check every source. Every trust has both scenarios happening on the same ward on the same day.
Common medicines reconciliation mistakes
1. Relying on a single source
The most common cause of missed medicines. A GP list on its own catches nothing bought over the counter, nothing herbal, and nothing recently changed. A patient interview on its own misses what the patient has forgotten to mention. Always compare at least two.
2. Skipping the OTC and herbal question
Patients rarely volunteer “I take some ibuprofen from the supermarket every day for my knee” unless you ask. Herbal supplements can be significant, especially St John’s wort with SSRIs, warfarin with a long list of teas, or valerian with sedatives. Ask specifically. Ask by category.
3. Not documenting the rationale for a change
Every medicine that has been added, stopped or changed since the last outpatient list needs a documented reason. “Discontinued” on its own is a red flag for the next clinician. Was it a side effect? An adverse event? Patient choice? Did it not work? Without the reason, the next team may restart the same medicine and the same error follows the patient.
4. Ignoring the community pharmacy record
Compliance data lives in dispensing records. If a monthly medicine has not been collected in three months, treat that as a signal, not a fact. Ask the patient why. Explore whether there was a side effect, a cost issue, a memory problem, or a simple change the GP had not been told about.
5. Reconciling once and not repeating at transfer or discharge
Admission reconciliation catches the errors coming in. Transfer reconciliation catches medicines that were started acutely and should have been stopped. Discharge reconciliation is the last chance to make sure the patient will actually take at home what the team intended them to take. Skip any of the three and errors slip through.
Medicines that need extra checks
Standard medicines reconciliation confirms what the patient is taking. For a specific group of medicines, that isn’t enough. Certain drugs come with mandatory safety checks that have to be verified alongside the reconciliation. Miss one and the list looks reconciled but is still dangerous.
The examples below are the ones UK pharmacy teams meet most often. It is not exhaustive. Use it as a prompt to build your own checklist for the medicines you dispense day to day.
Clozapine
Brand consistency is critical — Clozaril, Denzapine and Zaponex are each registered separately, so the patient must stay on the same brand as the one their monitoring service registration was set up with. Check the last FBC result (green, amber or red), the monitoring interval, and that registration with the correct service (ZTAS, DMS or MDS) is active and current. Any missed doses for more than 48 hours trigger re-titration. Ask the patient about any missed days, sore throats or infection symptoms.
Methotrexate
Once-weekly dose. Confirm the day of the week the patient takes it, the strength (usually 2.5 mg tablets, occasionally 10 mg — but never mixed), and total weekly dose in numbers of tablets. Check recent FBC and LFTs are on file, and that folic acid is co-prescribed. Ask about new respiratory symptoms, mouth ulcers or infection. Never accept a daily dose of oral methotrexate without querying it.
Lithium
Serum level (target usually 0.4–1.0 mmol/L for maintenance, higher in acute mania). Timing of the last level relative to the dose — a 12-hour trough is what’s comparable. Recent U&Es and TFTs. Brand consistency where possible — formulations differ in bioavailability. Ask about signs of toxicity: tremor, confusion, diarrhoea, unsteady gait.
DOACs (apixaban, rivaroxaban, dabigatran, edoxaban)
Indication (AF, VTE, thromboprophylaxis) drives the dose. Renal function is essential — dose adjustment is needed for reduced creatinine clearance, and dabigatran is contraindicated below CrCl 30. For dabigatran and edoxaban, weight matters too. Check for other bleeding-risk medicines added at admission (NSAIDs, SSRIs, dual antiplatelet).
Warfarin
Current INR and target range. Indication. Yellow book or anticoagulant service record. Any interacting medicines started or stopped recently — antibiotics, amiodarone, statins and many others push the INR around. Ask about bleeding, bruising, and whether the patient is confident with dose changes.
Depot antipsychotics
Brand, dose, injection interval and the date of the last dose. Confirm whose care the patient is under (community mental health team, ward, key worker) and when the next injection is due. Missed intervals often need loading. Also worth checking the concurrent oral antipsychotic dose — overlaps happen at admission and discharge.
Immunosuppressants (tacrolimus, ciclosporin, sirolimus)
Brand-specific. Formulations are not interchangeable — a switch from Prograf to Advagraf or generic tacrolimus requires supervised dose adjustment and repeat level monitoring. Check the last trough level, target range for the indication, U&Es, and any recent changes to interacting medicines (macrolides, azole antifungals, calcium-channel blockers, grapefruit).
Amiodarone
Long half-life makes reconciliation tricky. A patient may have “stopped” three weeks ago but still be pharmacologically loaded. Check baseline TFTs, LFTs and CXR. Ask about vision changes, tremor, dyspnoea and photosensitivity. Watch for interactions with warfarin, digoxin and statins.
Insulin
Reconcile in units, never mL. Confirm device (pen, cartridge, vial), brand and concentration — U-100 vs U-200 vs U-300 mistakes have killed people. Basal vs bolus vs mixed. Titration pattern. Recent HbA1c. Ask what the patient actually does with dose adjustments and what their carb-counting looks like if applicable.
Whatever the medicine, the principle is the same: if the drug has ongoing monitoring, brand-specific handling, or dose adjustment based on labs, the reconciliation isn’t complete until those checks are done and documented. If the patient can’t tell you their last blood test result or their next monitoring appointment, that’s a discrepancy in itself.
Explore PPets
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Medicines reconciliation FAQ
What is medicines reconciliation?
Medicines reconciliation is the structured process of building the most accurate possible list of every medicine a patient is taking, comparing it with what has been prescribed at admission, transfer or discharge, and resolving every discrepancy. It sits at the heart of UK hospital medicines safety and is a core role for pharmacy technicians.
Who does medicines reconciliation in a UK hospital?
Most UK hospital medicines reconciliation is carried out by pharmacy technicians, supported by pharmacists for clinical decisions. Some trusts train nursing or medical staff to do initial reconciliation, but the depth and consistency of pharmacy-technician-led reconciliation is why the role has grown so significantly over the last decade.
When should medicines reconciliation happen?
NICE guidance (NG5) recommends completion within 24 hours of adult admission. It should also happen at transfer between wards or care settings, and again at discharge before any prescription is issued. Earlier is always better. Errors caught in the first few hours prevent doses being missed or wrong doses being given.
How many sources should you compare?
At least two independent sources. The strongest combinations pair a patient-based source (interview, medicines brought in) with a system-based source (GP summary, community pharmacy dispensing record). Relying on a single source is the most common cause of missed medicines and out-of-date lists.
What counts as a discrepancy?
Any difference between what the patient is actually taking and what is recorded. Common examples include an omitted regular medicine, a duplicated therapy, a dose or frequency that has changed since the last GP letter, an OTC or herbal medicine the prescriber did not know about, an allergy not documented, and a medicine the patient has stopped but which still appears on the record.
How can pharmacy teams train medicines reconciliation?
Most med rec skill is built on the wards or at the counter, one case at a time, with a mentor watching. In hospital that means shadowing a senior pharmacy technician until you’ve done enough admissions to trust your own instincts. In community pharmacy it often means learning through DMS and NMS conversations. Formal courses on medicines optimisation, structured medication reviews and prescribing help, and PPets Connect gives you a free 30-minute chat with Daniel Dicker if you want to talk through your practice or your next career step.
Is medicines reconciliation only a hospital job?
No. Community pharmacy carries a huge share of the ongoing reconciliation work. The Discharge Medicines Service (DMS) refers patients from hospital to their community pharmacy for a medication review 7–14 days after discharge. The New Medicine Service (NMS) checks patients starting a new medicine for a long-term condition. Every repeat prescription that comes across the counter is another chance to catch a change the patient wasn’t told about. Hospital and community teams solve the same problem from different ends.
Want to talk med rec through?
Book a free 30-minute Microsoft Teams call with Daniel. He’s a UK-registered pharmacy technician with hospital and clinical experience and has trained hundreds of pharmacy technicians on Level 2 and Level 3 programmes.
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