Drug interactions
Tofacitinib + Trastuzumab deruxtecan
Severity: Major
Tofacitinib and Trastuzumab deruxtecan: major 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
Trastuzumab deruxtecan causes neutropenia and lymphopenia, and tofacitinib adds immunosuppression, so the risk of serious infection may increase.
What this interaction means in plain words
Tofacitinib and Trastuzumab deruxtecan can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Tofacitinib belongs to Musculoskeletal; Trastuzumab deruxtecan belongs to Oncology.
Why it happens
Additive myelosuppression and immunosuppression.
What to do
Monitor blood counts and signs of infection closely, and consider interrupting tofacitinib if severe neutropenia or infection develops.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Tofacitinib
- Baricitinib + Tofacitinib Contraindicated
- Cladribine + Tofacitinib Contraindicated
- Tofacitinib + Upadacitinib Contraindicated
- Abatacept + Tofacitinib Major
- Anti-thymocyte + Tofacitinib Major
- Antithymocyte globulin equine + Tofacitinib Major
Other interactions of Trastuzumab deruxtecan
Frequently asked questions
Can I take Tofacitinib with Trastuzumab deruxtecan?
MediHelp rates the interaction as major. Tofacitinib and Trastuzumab deruxtecan can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Trastuzumab deruxtecan causes neutropenia and lymphopenia, and tofacitinib adds immunosuppression, so the risk of serious infection may increase.
How serious is the interaction between Tofacitinib and Trastuzumab deruxtecan?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor blood counts and signs of infection closely, and consider interrupting tofacitinib if severe neutropenia or infection develops.
What other medicines interact with Tofacitinib?
MediHelp also lists interactions of Tofacitinib with, for example, Baricitinib, Cladribine, Upadacitinib. The full list is on the Tofacitinib page.
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