Erlotinib Tablets and Jantoven

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.

Erlotinib may increase the effects of warfarin and cause you to have bleeding complications. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. Call your doctor promptly if you experience any unusual bleeding or bruising, swelling, vomiting, blood in your urine or stools, headache, dizziness, or weakness during treatment with these medications. 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.

MONITOR: Erlotinib may potentiate the hypoprothrombinemic effect of warfarin and other oral anticoagulants. The mechanism of interaction is unknown, but may involve displacement of warfarin from protein-binding sites and/or competitive inhibition of R(+) warfarin metabolism via CYP450 3A4 and 1A2. Altered coagulation parameters and/or gastrointestinal bleeding have been reported during clinical trials. A postmarketing case report describes a 47-year-old patient with advanced lung cancer who developed an elevated INR and elbow hematoma following the addition of erlotinib to a stabilized warfarin regimen of 2.5 mg daily. His INR increased from 2.8 to 5.3 seven days after the initiation of erlotinib therapy, with no concurrent changes in warfarin dosage, other medications (except for loperamide to treat erlotinib-induced diarrhea), or diet. Two doses of warfarin was withheld on days 8 and 9, but the patient's INR continued to increase and he developed swelling and bruising over his right elbow. Anticoagulation was rapidly reversed following the administration of subcutaneous phytonadione. The patient opted to discontinue erlotinib therapy on day 9, and the next day his INR was 2.4.

MANAGEMENT: Caution is advised during coadministration of warfarin and erlotinib. The INR should be checked frequently and warfarin dosage adjusted accordingly, particularly following initiation, discontinuation or change of dosage of erlotinib in patients who are stabilized on their warfarin regimen. The same precaution may be applicable during therapy with other oral anticoagulants, although clinical data are lacking. Patients should be advised to promptly report any signs of bleeding to their doctor, including pain, swelling, headache, dizziness, weakness, prolonged bleeding from cuts, increased menstrual flow, vaginal bleeding, nosebleeds, bleeding of gums from brushing, unusual bleeding or bruising, red or brown urine, or red or black stools.

Erlotinib Tablets

Generic Name: erlotinib

Brand name: Tarceva

Synonyms: Erlotinib

What is Erlotinib Tablets?

Jantoven

Generic Name: warfarin

Brand name: Coumadin, Jantoven

Synonyms: n.a.

What is Jantoven?