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Drug interactions

Cobicistat + Palbociclib

Severity: Major

Cobicistat and Palbociclib: 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

Cobicistat is a strong CYP3A inhibitor that can markedly increase palbociclib exposure. This raises the risk of neutropenia and other toxicities.

What this interaction means in plain words

Cobicistat and Palbociclib 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.

Cobicistat belongs to Miscellaneous; Palbociclib belongs to Oncology.

Evidence level: Moderate

Why it happens

Strong mechanism-based CYP3A inhibition by cobicistat decreases palbociclib clearance.

What to do

Avoid the combination if possible. If unavoidable, reduce palbociclib to 75 mg daily and monitor blood counts closely.

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?

Bring a full list of your medicines, including over-the-counter products, supplements and herbal remedies, to every pharmacy visit.

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Frequently asked questions

Can I take Cobicistat with Palbociclib?

MediHelp rates the interaction as major. Cobicistat and Palbociclib 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. Cobicistat is a strong CYP3A inhibitor that can markedly increase palbociclib exposure. This raises the risk of neutropenia and other toxicities.

How serious is the interaction between Cobicistat and Palbociclib?

MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination if possible. If unavoidable, reduce palbociclib to 75 mg daily and monitor blood counts closely.

What other medicines interact with Palbociclib?

MediHelp also lists interactions of Palbociclib with, for example, Apalutamide, Atazanavir, Carbamazepine. The full list is on the Palbociclib 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.

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