Amiodarone/Coumarin Anticoagulants Interactions

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Serious. These medicines may interact and cause very harmful effects. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

When these two medicines are taken together, amiodarone may prevent your body from processing your anticoagulant properly.

What might happen:

You may experience an increased chance for bleeding, including bleeding from your gums, nosebleeds, unusual bruising, or dark stools.

What you should do about this interaction:

Make sure your healthcare professionals (e.g. doctor or pharmacist) know you are taking these two medicines together. They may already be aware of this interaction and may be monitoring you for it. If your doctor prescribes these medicines together, your anticoagulant dose may be reduced and your bleeding times (e.g. INR test) will need to be checked more often. Do not start, stop, or change the dosage of any medicine before checking with them first.

View Reference
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