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:
The cause of this interaction is not known. When these two medicines are taken together, dextrothyroxine may decrease the ability of your blood to form clots.
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:
Contact your healthcare professionals (e.g. doctor or pharmacist) as soon as possible about taking these two medicines together. They may already be aware of this drug interaction and may be monitoring you for it. If your doctor prescribes these medicines together, you may need to check your bleeding times more often. Do not start, stop, or change the dosage of any medicine before checking with them first.
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