Warfarin review

Safety advisory

16 February 2015

Consumers and health professionals are advised that the TGA has completed a review of the Product Information (PI) for goods containing warfarin.

Warfarin is an anticoagulant that is used for the prevention and treatment of problems associated with blood clots including venous thrombosis and pulmonary embolism, and some heart conditions in which blood vessels become blocked.

Two medicines that contain warfarin are marketed in Australia, Coumadin and Marevan.

Review findings

The review involved evaluation of the PIs and relevant medical literature, and expert advice from the Advisory Committee on the Safety of Medicines.

The TGA found that the PI for warfarin required an update for clarity and inclusion of important clinical information.

Proposed changes relate to potential drug interactions, patient monitoring for anticoagulant status and treatment of overdose.

The TGA is working with the sponsor to update the PI to provide clearer and more up-to-date information.

Further details of the proposed changes to the PI will be provided in a future alert.

Information for consumers

Consumers are reminded that warfarin may interact with other medications, including herbal/complementary medicines. These interactions may result in serious bleeding events.

If you are being treated with an anticoagulant it is important that you inform treating health professionals of any other medicines you are taking, including herbal/complementary remedies.

Consumers are also reminded that the safe use of warfarin requires frequent patient monitoring.

Information for health professionals

Health professionals are reminded that the safety of warfarin is maintained by frequent monitoring of the International Normalised Ratio.

The major causes of bleeding with warfarin include the concomitant use of antiplatelet agents, anticoagulants and non-steroidal anti-inflammatory drugs, and concomitant use of medicines that alter the metabolism of warfarin.

Reporting problems

Consumers and health professionals are encouraged to report problems with medicines or vaccines. Your report will contribute to the TGA's monitoring of these products.

The TGA cannot give advice about an individual's medical condition. You are strongly encouraged to talk with a health professional if you are concerned about a possible adverse event associated with a medicine or vaccine.