Coumadin and Oritavancin Diphosphate

In the database of official manuals used in the service creation an interaction registered by statistical results of studies was found, which can either lead to negative consequences for the patient health or strengthen a mutual positive effect. A doctor should be consulted to address the issue of joint drug administration.

Treatment with oritavancin may increase the blood levels and effects of warfarin and cause you to bleed more easily. You may need a dose adjustment or more frequent monitoring of your prothrombin time or INR to safely use both medications. Talk to your doctor if you have any questions or concerns. Your doctor may already be aware of the interaction, but has determined that this is the best course of treatment for you and has taken appropriate precautions and is monitoring you closely for any potential complications. You should seek immediate medical attention if you experience any unusual bleeding or bruising, or have other signs and symptoms of bleeding such as dizziness; lightheadedness; red or black, tarry stools; coughing up or vomiting fresh or dried blood that looks like coffee grounds; severe headache; and weakness. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

GENERALLY AVOID: Coadministration with oritavancin may increase the plasma concentrations of warfarin. The proposed mechanism is inhibition of the CYP450 2C9-mediated metabolism of warfarin by oritavancin, a weak inhibitor of the isoenzyme. In healthy volunteers, a single 1200 mg dose of oritavancin increased warfarin systemic exposure (AUC) by 31%. The risk of bleeding may be increased. In addition, the use of oritavancin may temporarily interfere with the therapeutic monitoring of warfarin therapy. Oritavancin has been shown to artificially prolong the prothrombin time (PT) or INR for up to 12 hours following a single 1200 mg dose by binding to and preventing the action of the phospholipid reagents that activate coagulation in commonly used laboratory coagulation tests. Oritavancin does not affect the coagulation system in vivo, however.

MANAGEMENT: Oritavancin should only be administered to patients on chronic warfarin therapy when the benefits are expected to outweigh the risk of bleeding. Clinicians should be aware that the therapeutic monitoring of warfarin may be unreliable up to 12 hours after oritavancin dosing. The same precaution may be applicable to other coumarin anticoagulants that are metabolized by CYP450 2C9 (e.g., acenocoumarol).

Coumadin

Generic Name: warfarin

Brand name: Coumadin, Jantoven

Synonyms: n.a.

What is Coumadin?

Oritavancin Diphosphate

Generic Name: oritavancin

Brand name: Orbactiv

Synonyms: Oritavancin

What is Oritavancin Diphosphate?