Erlotinib; Gefitinib; Sorafenib/Warfarin
How the interaction occurs:
Both of these medicines can interfere with your body's ability to make blood clots.
What might happen:
You may experience an increased chance for bleeding including bleeding from your gums, nosebleeds, unusual bruising, or dark stools.
What you should do about this interaction:
Ask your healthcare professionals (e.g. doctor or pharmacist) about taking these medicines together. If your doctor prescribes these medicines together, you may need to have your bleeding times checked more often. 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.
1.Tarceva (erlotinib) US prescribing information. Genentech, Inc. April, 2012.
2.Iressa (gefitinib) US prescribing information. AstraZeneca March 6, 2012.
3.Nexavar (sorafenib) US prescribing information. Bayer Pharmaceuticals Corporation November, 2013.
4.Thomas KS, Billingsley A, Amarshi N, Nair BA. Elevated international normalized ratio associated with concomitant warfarin and erlotinib. Am J Health Syst Pharm 2010 Sep 1;67(17):1426-9.
5.Arai S, Mitsufuji H, Nishii Y, Onoda S, Ryuge S, Wada M, Katono K, Iwasaki M, Takakura A, Otani S, Yamamoto M, Yanaihara T, Yokoba M, Kubota M, Katagiri M, Fukui T, Kobayashi H. Yanase N, Hataishi R, Masuda, N. Effect of gefitinib on warfarin antithrombotic activity. Int J Clin Oncol 2009 Aug;14(4):332-6.
6.Onoda S, Mitsufuji H, Yanase N, Ryuge S, Kato E, Wada M, Ishii K, Hagiri S, Yamamoto M, Yokoba M, Yanaihara T, Kuboto M, Takada N, Katagiri M, Abe T, Tanaka N, Kobayashi H, Masuda N. Drug interaction between gefitinib and warfarin. Jpn J Clin Oncol 2005 Aug;35(8):478-82.
7.Shiozawa K, Watanabe M, Hirano N, Wakui N, Kikuchi Y, Hara F, Ishii K, Iida K, Sumino Y. Gastrointestinal hemorrhage associated with concurrent use of sorafenib and warfarin for hepatocellular carcinoma. Gan To Kagaku Ryoho 2011 Oct;38(10):1713-5.
8.Moretti LV, Montalvo RO. Elevated International Normalized Ratio associated with concurrent use of sorafenib and warfarin. Am J Health Syst Pharm 2009 Dec 1;66(23):2123-5.