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British Journal of Clinical Pharmacology logoLink to British Journal of Clinical Pharmacology
. 1986 Jul;22(1):37–41. doi: 10.1111/j.1365-2125.1986.tb02877.x

Investigation of patients with abnormal response to warfarin.

D P Bentley, G Backhouse, A Hutchings, R L Haddon, B Spragg, P A Routledge
PMCID: PMC1401092  PMID: 3741725

Abstract

In 55 patients in whom warfarin control had been satisfactory for at least 4 months, warfarin dose, plasma warfarin concentration and plasma clearance were measured. The mean dose to maintain the BCR (INR) between 2.3 and 3.3 was 5.1 +/- 2 mg day-1 (range 1.5-10 mg). Plasma warfarin concentrations and warfarin clearance were log-normally distributed with 95% confidence limits between 0.8 and 2.4 mg l-1 and 2.5 and 8.71 day-1 respectively. These confidence limits were used to construct algorithms which correctly predicted the cause of abnormal warfarin sensitivity in two patients and resistance in two further patients. These algorithms should help to identify the cause of abnormal warfarin responsiveness in the clinical setting.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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