Selected Anticoagulants (Vit K antag)/Selected Penicillins 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:

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:

The cause of the interaction is not known.

What might happen:

Amoxicillin or large doses of injectable penicillin may cause an increased chance of bleeding including bleeding from your gums, nosebleeds, unusual bruising, or dark stools.

What you should do about this interaction:

Contact your healthcare professional (e.g. doctor or pharmacist) about taking these two medicines together. If your doctor prescribes these medicines together, you may need to check your bleeding times more often. Patients with kidney failure may be more likely to experience this interaction, so let your doctor know if you have kidney problems.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.

View Reference
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