Medication review — polypharmacy and the unsafe combinations
PLAB 2 & PRES 3 · prescribing / elderly medicine · hard · 10 minutes
Candidate brief
You are an FY2 doctor in a GP surgery. Mrs Dorothy Ainsley, 84, has been booked for a structured medication review after a fall at home last week (no fracture; she was seen in the emergency department and discharged). Her daughter, who is present, says her mother has become "groggy, forgetful and constipated" over the past year. Her current repeat prescription list is: 1. Amitriptyline 25 mg at night — started years ago "for sleep" 2. Oxybutynin 5 mg twice daily — for an overactive bladder 3. Codeine phosphate 30 mg, up to four times daily as required — for knee osteoarthritis (she takes it most days, twice daily) 4. Paracetamol 1 g four times daily 5. Zopiclone 3.75 mg at night as required — "most nights" 6. Sertraline 100 mg daily — for depression, 2 years 7. Amlodipine 5 mg daily 8. Bendroflumethiazide 2.5 mg daily 9. Omeprazole 20 mg daily — started during a hospital admission 3 years ago 10. Atorvastatin 20 mg daily Observations today: BP lying 128/76 mmHg, standing 104/62 mmHg. Recent bloods: sodium 131 mmol/L, eGFR 44. Please review the list, identify the unsafe combinations, and agree a plan with Mrs Ainsley and her daughter.
What examiners look for
Polypharmacy harm is usually arithmetic, not a single bad drug. Three anticholinergics, three sedatives, two sodium-lowerers and three blood-pressure droppers — each defensible alone, together they are a fall, a fog and a sodium of 131. The review skill is reading the list as one prescription, because that is how the patient takes it. Every symptom she brought is on the drug chart: dry mouth (anticholinergics), constipation (anticholinergics + codeine), grogginess and forgetfulness (sedative stack + anticholinergic burden), the fall (postural drop + sedation). Before diagnosing dementia or ageing in an older person, subtract the medicines from the presentation — you will often subtract the presentation too. Prescribing cascades and legacy prescriptions fill repeat lists: a PPI that outlived its NSAID by three years, a sleeping tablet that outlived its bereavement course by twenty. "Started during an admission" and "started years ago for sleep" are diagnoses of the list itself — ask every drug what it is currently FOR. Deprescribing is a procedure with technique: one or two changes at a time, taper what cannot stop (hypnotics, tricyclics, antidepressants), replace with non-drug measures, monitor the specific harms (BP and U&E after diuretic changes), and book the review before the patient leaves. Stop-everything heroics cause withdrawal, rebound and a patient who never trusts a review again. And do not only subtract. A structured review also starts what is missing (the START to the STOPP): bone protection after a fall, vitamin D, vaccination, physiotherapy, a pendant alarm offered without the word "old". A list that is shorter AND a patient who is safer — that is the outcome measure.
Guideline references
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