Pharmacy World and Science

, Volume 26, Issue 4, pp 232–237 | Cite as

Evaluation of warfarin dosing by pharmacists for elderly medical in-patients

  • Naomi Burns


Setting: Brighton and Sussex University Hospitals NHS Trust (BSUH).

Method: Two wards at Brighton General Hospital were under pharmacist-control of warfarin dosing and three wards remained under the care of doctors. Data was collected for 11 months and a total of 33 patients were recruited into each arm.

Results: Pharmacists prescribed more appropriate loading and maintenance doses (according to the Trust’s Prescribing Guidelines) compared to doctors. This resulted in more patients reaching their target INR sooner. Documentation of indication, duration of treatment and target INR was also much improved compared to medical staff. However, more patients (73%) in the doctors’ group were within range on discharge and at the out-patient clinic (79%), compared to the pharmacists (68% & 61% respectively). This could not be explained entirely. Significantly fewer patients dosed by pharmacists had episodes of over or under anti-coagulation (91% vs 67%) and fewer INR tests were requested (2.3/patient/week) compared to those dosed by doctors (2.7).

Patients under the control of pharmacists also had fewer adverse events (6% vs 12%). One major GI bleed occurred in the doctors’ group.

Conclusion: Pharmacist dosing of warfarin for in-patients had a beneficial effect on most aspects of anti- coagulation control. This study therefore provides further evidence to support the extended role pharmacists can play with the benefit of reducing risk, junior doctors’ hours and improving patient care.

Anti-coagulation Effectiveness Evaluation Guideline adherence In-patients Pharmacist prescribing United Kingdom Warfarin 


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  1. 1.
    Sinha U, Raha S, Wilkins E. Adverse drug reactions and hospital admission of older patients [letter]. Age Ageing 2000; 29: 551–2.Google Scholar
  2. 2.
    Lee Y, Schommer JC. Effect of a pharmacist managed anti-coagulant clinic on warfarin related hospital re-admissions. Am J Health Syst Pharm 1996; 53: 1580–3.Google Scholar
  3. 3.
    Medication Error Review Group. Medication error report. Brighton Health Care NHS Trust 1999.Google Scholar
  4. 4.
    Gray DR, Garabedian-Ruffalo SM, Chretien SD. Cost-justification of a clinical pharmacist-managed anti-coagulation clinic. Drug Intell Clin Pharm 1985; 19: 575–80.Google Scholar
  5. 5.
    Cohen IA, Hutchison TA, Kirking DM, Shue ME. Evaluation of a pharmacist managed anti-coagulation clinic. J. Clin Hosp Pharm 1985; 10: 167–75.Google Scholar
  6. 6.
    Garabedian-Ruffalo SM, Gray DR, Sax MJ, Ruffalo,RL. Retrospective evaluation of a pharmacist-managed warfarin anti-coagulation clinic. Am J Hosp Pharm 1985; 42: 304–8.Google Scholar
  7. 7.
    Ellis RF, Stephens MA, Sharp GB. Evaluation of a pharmacy-managed warfarin monitoring service to co-ordinate inpatient and out-patient therapy. Am J Hosp Pharm 1992; 49: 387–94.Google Scholar
  8. 8.
    Dager WE, Branch JM, King JH. Optimisation of in-patient warfarin therapy: impact of daily consultation by a pharmacist managed anti-coagulation service. Ann Pharmacother 2000; 34: 567–72.Google Scholar
  9. 9.
    Patel P, Luckitt J. A pharmacist led service for in-patient anti-coagulation. Thrombus 2002; 6: 9–11.Google Scholar
  10. 10.
    Taylor M, Rhodes S, Bond S et al. An anti-coagulation service in evolution. Thrombus 2001; 5: 6–7.Google Scholar
  11. 11.
    Boddy C. Pharmacist involvement with warfarin dosing for inpatients. Pharm World Sci 2001; 23: 31–5.Google Scholar
  12. 12.
    Department of Health. Implementing the European working time directive for doctors in training. HSC 2003/001. London: Department of Health, 3 January 2003.Google Scholar
  13. 13.
    Guidelines on Oral Anticoagulation. Br J Haematol 1998; 101: 374–87.Google Scholar
  14. 14.
    Dobrzwski S. Predicting Warfarin Dosage. J Clin Hosp Pharm 1983; 8: 247–50.Google Scholar

Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • Naomi Burns
    • 1
  1. 1.Clinical Pharmacy Services ManagerBrighton General HospitalBrightonUK

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