prescribing in geriatrics

• Learning Outcomes


  • Understand the pharmacokinetic changes that occur in normal process of aging
  • Apply these concepts to a worked example of a complex patient
  • Understand the various prescribing tools that are used to promote safe and appropriate prescribing in an older population
• Medication History


  • Naproxen 500 mg BD
  • Metformin 1g BD
  • Amitriptyline 50 mg nocte
  • Aspirin 150 mg daily
  • Digoxin 125 mcg daily
  • Amlodipine 10 mg daily
  • Senna 15 mg nocte
  • Prednisolone 30 mg OD
  • Amoxicillin 500 mg TDS
  • Atenolol 50 mg daily
  • Gliclazide 80 mg BD
  • Diazepam 5 mg TDS
  • Paracetamol 1 g QDS
  • Hydrocortisone cream BD
  • Levothyroxine 100 mcg OD
  • Bendroflumethiazide 2.5 mg
  • Simvastatin 40 mg nocte
• (Hyper)polypharmacy is Common
• We are Driven by Guidelines
• Boyd C, et al.: 'Clinical practice guidelines and quality of care for older patients with multiple comorbid diseases: implications for pay for performance. JAMA. 2005; 294(6): 716-24'
• Rochon PA, Gurwitz JH: 'Optimising drug treatment for elderly people: the prescribing cascade. BMJ. 1997; 315(7115): 1096-9'
• Challenges in Prescribing for Older Patients
• Changes in processes


  • Absorption
  • Distribution
  • Metabolism
  • Excretion
  • Tissue sensitivity
• Risk of NSAID-related gastrointestinal bleeding or death by age

  • Age range
  • Number
  • Number with
  • Chance of GI bleed
  • Chance of dying from GI bleed
• Data categories


  • Age
  • Age range
  • Number
  • Number with
  • Chance of GI
  • Chance of dying
  • Solution
  • Protein binding
  • Changes in Hepatic Function
  • Changes in Renal Function
• Recalculated for a PCG of 100,000 people from original data from: AL Blower, et al. Emergency admissions for upper gastrointestinal disease and their relation to NSAID use. Aliment Pharmacol Ther. 1997; 11: 283-91.
• Naproxen 500 mg BD
• Metformin 1g BD
• Amitriptyline 50 mg nocte
• Aspirin 150 mg daily
• Digoxin 125 mcg daily
• Amlodipine 10 mg daily
• Senna 15 mg nocte
• Prednisolone 30 mg OD
• Amoxicillin 500 mg TDS
• Atenolol 50 mg daily
• Gliclazide 80 mg BD
• Diazepam 5 mg TDS
• Paracetamol 1 g QDS
• Hydrocortisone cream BD
• Levothyroxine 100 mcg OD
• Bendroflumethiazide 2.5 mg
• Simvastatin 40 mg nocte
• Should we swap the Naproxen?
• Upton et al. Naproxen pharmacokinetics in the elderly. Br J Clin Pharmacol. 1984; 18(2): 207–214.
• Baigent et al. Vascular and upper gastrointestinal effects of non-steroidal anti-inflammatory drugs: meta-analyses of individual participant data from randomised trials. Lancet. 2013; 382(9894): 769–779.
• McGettigan P, Henry D. Cardiovascular risk and inhibition of cyclooxygenase: a systematic review of the observational studies of selective and nonselective inhibitors of cyclooxygenase 2. JAMA. 2006; 296(13): 1633-44.
• Changes in Hepatic Function
• Changes in Renal Function
• The oxidative metabolism of diazepam is mediated by CYP3A and CYP2C19 isoenzymes to hydroxydiazepam (temazepam) and nordiazepam (t1/2 approximately 96 hours)
• We could, therefore, either: Prolong the time between diazepam doses or Replace with temazepam, oxazepam or lorazepam or ‘Deprescribe’ the benzodiazepine
• What does the BNF say?
• Hydroxydiazepam (temazepam) and nordiazepam have a half-life of approximately 96 hours
• Options for managing benzodiazepine use

  • Prolong the time between diazepam doses
  • Replace with temazepam, oxazepam or lorazepam
  • 'Deprescribe' the benzodiazepine
• Medications in use


  • Naproxen 500 mg BD
  • Metformin 1g BD
  • Amitriptyline 50 mg nocte
  • Aspirin 150 mg daily
  • Digoxin 125 mcg daily
  • Amlodipine 10 mg daily
  • Senna 15 mg nocte
  • Prednisolone 30 mg OD
  • Amoxicillin 500 mg TDS
  • Atenolol 50 mg daily
  • Gliclazide 80 mg BD
  • Diazepam 5 mg TDS
  • Paracetamol 1 g QDS
  • Hydrocortisone cream BD
  • Levothyroxine 100 mcg OD
  • Bendroflumethiazide 2.5 mg
  • Simvastatin 40 mg nocte