Lapatinib with Eltrombopag Interaction Details
Brand Names Associated with Lapatinib
- Lapatinib
- Tykerb®
Brand Names Associated with Eltrombopag
- Eltrombopag
- Promacta®

Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
Dec 20, 2023
Interaction Effect
Increased exposure of BCRP substrate
Interaction Summary
Coadministration of eltrombopag and a BCRP substrate may result in increased exposure of the BCRP substrate. If concomitant use is required, use caution and monitor patients closely for signs and symptoms of excessive BCRP substrate exposure. Consider reducing the dose of these drugs if necessary.
Severity
Moderate
Onset
Unspecified
Evidence
Probable
How To Manage Interaction
Coadministration of eltrombopag and a BCRP substrate may result in increased exposure of the BCRP substrate. If concomitant use is required, use caution and monitor patients closely for signs and symptoms of excessive BCRP substrate exposure. Consider reducing the dose of these drugs if necessary.
Mechanism Of Interaction
Inhibition of BCRP-mediated substrate metabolism by eltrombopag
Lapatinib Overview
-
Lapatinib is used with capecitabine (Xeloda) to treat a certain type of advanced breast cancer in people who have already been treated with other chemotherapy medications. Lapatinib is also used with letrozole (Femara) to treat a certain type of breast cancer in postmenopausal women (women who have experienced a change of life; end of menstrual periods) that has spread to other parts of the body. Lapatinib is in a class of medications called kinase inhibitors. It works by blocking the action of the abnormal protein that signals cancer cells to multiply. This helps stop or slow the spread of cancer cells.
Eltrombopag Overview
-
Eltrombopag is used to increase the number of platelets (cells that help the blood clot) to decrease the risk of bleeding in adults and children 1 year of age and older who have chronic immune thrombocytopenia (ITP; an ongoing condition that may cause unusual bruising or bleeding due to an abnormally low number of platelets in the blood) and who have not been helped or cannot be treated with other treatments, including medications or surgery to remove the spleen. Eltrombopag is also used to increase the number of platelets in people who have hepatitis C (a viral infection that may damage the liver) so that they can begin and continue treatment with interferon (Peginterferon, Pegintron, others) and ribavirin (Rebetol). Eltrombopag is also used in combination with other medications to treat aplastic anemia (condition in which the body does not make enough new blood cells) in adults and children 2 years of age and older. It is also used to treat aplastic anemia in adults who have not been helped with other medications. Eltrombopag is used to increase the number of platelets enough to decrease the risk of bleeding in people with ITP or aplastic anemia, or to allow treatment with interferon and ribavirin in people with hepatitis C. However it is not used to increase the number of platelets to a normal level. Eltrombopag should not be used to treat people who have low numbers of platelets due to conditions other than ITP, hepatitis C, or aplastic anemia. Eltrombopag is in a class of medications called thrombopoietin receptor agonists. It works by causing the cells in the bone marrow to produce more platelets.
Return To Our Drug Interaction Homepage
Feedback, Question Or Comment About This Information?
Ask Dr. Brian Staiger, PharmD, our medical editor, directly! He's always more than happy to assist.
Definitions
Severity Categories
Contraindicated
These drugs, generally, should not be used together simultaneously due to the high risk of severe adverse effects. Combining these medications can lead to dangerous health outcomes and should be strictly avoided unless otherwise instructed by your provider.
Major
This interaction could result in very serious and potentially life-threatening consequences. If you are taking this drug combination, it is very important to be under close medical supervision to minimize severe side effects and ensure your safety. It may be necessary to change a medication or dosage to prevent harm.
Moderate
This interaction has the potential to worsen your medical condition or alter the effectiveness of your treatment. It's important that you are monitored closely and you potentially may need to make adjustments in your treatment plan or drug dosage to maintain optimal health.
Minor
While this interaction is unlikely to cause significant problems, it could intensify side effects or reduce the effectiveness of one or both medications. Monitoring for changes in symptoms and your condition is recommended, and adjustments may be made if needed to manage any increased or more pronounced side effects.
Onset
Rapid: Onset of drug interaction typically occurs within 24 hours of co-administration.
Delayed: Onset of drug interaction typically occurs more than 24 hours after co-administration.
Evidence
Level of documentation of the interaction.
Established: The interaction is documented and substantiated in peer-reviewed medical literature.
Theoretical: This interaction is not fully supported by current medical evidence or well-documented sources, but it is based on known drug mechanisms, drug effects, and other relevant information.
How To Manage The Interaction
Provides a detailed discussion on how patients and clinicians can approach the identified drug interaction as well as offers guidance on what to expect and strategies to potentially mitigate the effects of the interaction. This may include recommendations on adjusting medication dosages, altering the timing of drug administration, or closely monitoring for specific symptoms.
It's important to note that all medical situations are unique, and management approaches should be tailored to individual circumstances. Patients should always consult their healthcare provider for personalized advice and guidance on managing drug interactions effectively.
Mechanism Of Interaction
The theorized or clinically determined reason (i.e., mechanism) why the drug-drug interaction occurs.
Disclaimer: The information provided on this page is for informational purposes only and should not be considered medical advice. Always consult with a qualified healthcare professional regarding your specific circumstances and medical conditions.
Where Does Our Information Come From?
Information for our drug interactions is compiled from several drug compendia, including:
The prescribing information for each drug, as published on DailyMED, is also used.
Individual drug-drug interaction detail pages contain references specific to that interaction. You can click on the reference number within brackets '[]' to see what reference was utilized.
The information posted is fact-checked by HelloPharmacist clinicians and reviewed quarterly.