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, your body may process your blood-thinning medicine more quickly.
What might happen:
The effects of your blood-thinner may decrease and increase your risk for blood clots. If your rifamycin is stopped, there is an increased chance for bleeding.
What you should do about this interaction:
Contact your healthcare professionals (e.g. doctor or pharmacist) about taking these two medicines together. They may already be aware of this interaction and may be monitoring you for it. For some anticoagulants, your doctor may want to check your bleeding times more often. Your dose of blood-thinner may need adjusting, especially if your doctor stops your rifamycin. If you experience bleeding from your gums, nosebleeds, unusual bruising, or dark stools, contact your doctor. Do not start, stop, or change the dosage of any medicine before checking with them first.
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