Drug interactions
Belimumab + Trastuzumab
Severity: Moderate
Belimumab and Trastuzumab: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Belimumab can increase the risk of infections through B-cell survival inhibition, and trastuzumab with chemotherapy may add neutropenia. The combination has not been well studied and the added risk is mainly theoretical.
What this interaction means in plain words
Belimumab and Trastuzumab can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Belimumab belongs to Miscellaneous; Trastuzumab belongs to Oncology.
Why it happens
Additive immunosuppression from BLyS inhibition and treatment-related neutropenia.
What to do
Monitor for infections and blood counts during combined therapy, and consider holding belimumab if a serious infection develops.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Belimumab and Trastuzumab, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 14 days on the web. No card needed.
Other interactions of Trastuzumab
Other interactions of Belimumab
- Belimumab + Measles mumps and rubella vaccine Major
- Abatacept + Belimumab Moderate
- Adalimumab + Belimumab Moderate
- Anakinra + Belimumab Moderate
- Anti-thymocyte + Belimumab Moderate
- Belimumab + Denosumab Moderate
Frequently asked questions
Can I take Belimumab with Trastuzumab?
MediHelp rates the interaction as moderate. Belimumab and Trastuzumab can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Belimumab can increase the risk of infections through B-cell survival inhibition, and trastuzumab with chemotherapy may add neutropenia. The combination has not been well studied and the added risk is mainly theoretical.
How serious is the interaction between Belimumab and Trastuzumab?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor for infections and blood counts during combined therapy, and consider holding belimumab if a serious infection develops.
What other medicines interact with Trastuzumab?
MediHelp also lists interactions of Trastuzumab with, for example, Daunorubicin, Doxorubicin liposomal, Doxorubicin. The full list is on the Trastuzumab page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
