|Title:||Rationalisation of Warfarin Brands|
|Document ID:||Operational Circular OP 1755/04|
|Date of issue:||Thursday, 25 March 2004|
|Description:||The Western Australian Therapeutic Advisory Group (WA.TAG) advises that all new patients commencing warfarin therapy in WA (in all sectors of medical practice and all pharmacies) should receive Marevan®. Coumadin® should be prescribed and supplied only to patients already stabilised on Coumadin® therapy.|
|Period of effect:||from 2 February 2004|
|Authorised by:||Dr Andrew Robertson, Director, Clinical Policy and Programs, 23-Mar-2004|
|Print version:||View print version|
Rationalisation of Warfarin Brands
The Western Australian Therapeutic Advisory Group (WA.TAG) recommends that:-
Marevan® should be regarded as the standard brand of warfarin for use throughout Western Australia, and should be preferentially stocked and prescribed for all new patients commencing warfarin therapy in WA. Hospitals currently stocking Coumadinâ as the preferred brand of warfarin should switch to Marevan®, with due attention to the points given below.
Two brands of warfarin (Marevan® and Coumadin®) are currently marketed in Australia by the Boots Company (Aust) Pty Ltd. These brands are not bioequivalent and have different tablet dose sizes. WA.TAG therefore considers that a preference should be assigned because of the potential for serious medication errors involving loss of anticoagulant control and the need to protect the safety and wellbeing of patients. WA.TAG has reviewed PBS and public hospital usage data for Western Australian and notes that Marevan® is prescribed in nearly all public hospitals, and is also the predominant brand of warfarin prescribed in the community. WA.TAG therefore strongly prefers Marevan®, based on the existing usage patterns in this State.
WA.TAG advises that all new patients commencing warfarin therapy in a WA (in all sectors of medical practice and all pharmacies) should receive Marevan®.
The alternative and less frequently used brand (Coumadin®) should not be substituted for Marevan® and the two brands should never be co-prescribed. Coumadin® should be prescribed and supplied only to patients already stabilised on Courmadin® therapy. Substituting or switching from Coumadin® to Marevan® in stabilised patients requires close monitoring and would normally only be considered if there was a clinical need or when recommencing therapy after a period without Coumadin®. Use of Coumadin® in WA is expected to diminish over time.
Similar initiatives have been made to rationalise warfarin brands in other States, but NSW and Victoria have established a preference for Coumadin®. It is vital that clinicians and pharmacists should determine the warfarin brand used by a patient who commenced treatment outside Western Australia to avoid inadvertent substitution of brands.
Dr Andrew Robertson
This circular last updated: Thursday, 25 March 2004 at 12:00am