How the interaction occurs:
When warfarin is taken with valproic acid, divalproex or valproate, your body may process your warfarin more slowly.
What might happen:
Your warfarin level may increase, leading to elevated prothrombin (PT or INR) laboratory tests. If the INR or prothrombin time is too high you have an increased chance for bleeding episodes such bleeding from your gums, nosebleeds, unusual bruising, or dark stools.
What you should do about this interaction:
Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together. You may need to have your INR or PT tests checked more often, especially when you first start taking valproic acid or if your dose changes. 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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