Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
When these two medicines are taken together, the antithyroid medication may cause your body to process vitamin-k slower. This may decrease the effects of the anticoagulant.
What might happen:
The effect of the blood-thinner may decrease.You may experience an increased chance for bleeding including bleeding from your gums, nosebleeds, unusual bruising, or dark stools if you stop taking the antithyroid drug.
What you should do about this interaction:
Ask your healthcare professionals (e.g. doctor or pharmacist) about taking these medicines together. If your doctor prescribes these medicines together, you may need to have your bleeding times checked more often. If you have any signs of bleeding, such as bleeding from your gums, nosebleeds, unusual bruising, or dark stools, contact your doctor right away.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
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