erlotinib, Tarceva (cont.)

Pharmacy Author:
Medical Editor:

Some drugs increase the elimination of erlotinib by increasing the activity of CYP3A4 enzymes. This reduces the levels of erlotinib in the body and may reduce its effect. Examples of such drugs include rifampicin (Rifadin), rifabutin (Mycobutin), rifapentine (Priftin), phenytoin (Dilantin), carbamazepine (Tegretol), phenobarbital and St. John's Wort. These drugs should be avoided in patients taking erlotinib, if possible. If alternative drugs are not an option, higher doses of erlotinib may be required.

Cigarette smoking also reduces the concentration of erlotinib in the blood. Patients are advised to quit smoking.

Drugs that reduce the production of acid in the stomach will reduce the absorption of erlotinib. Therefore, proton pump inhibitors (PPI's, for example, omeprazole [Prilosec, Zegerid]) should not be administered with erlotinib, and erlotinib should be administered 10 hours before H2-receptor blockers (for example, ranitidine [Zantac]) or two hours after taking the H2-receptor blocker.

Administration of antacids should be separated from administration of erlotinib by several hours.

Erlotinib has been associated with increased risk of bleeding, especially in patients also taking warfarin (Coumadin). Patients taking warfarin should be monitored closely.

PREGNANCY: Erlotinib has been shown to cause maternal toxicity and fetal death in rabbits given high doses of erlotinib. Even though there are no well-controlled studies in pregnant women using erlotinib, women of childbearing age should be advised to avoid pregnancy while on erlotinib.

NURSING MOTHERS: It is not known whether erlotinib is excreted in human milk. Because many medicines are excreted in human milk and because the effects of erlotinib on infants have not been studied, women should abstain from breastfeeding while receiving erlotinib.

Medically reviewed by Eni Williams, PharmD

Reference: FDA Prescribing Information

Medically Reviewed by a Doctor on 7/21/2015

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Pill Finder Tool

Need help identifying pills and medications?
Use the pill identifier tool on RxList.

Back to Medications Index