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Drug interactions

Aprepitant + Ritonavir

Severity: Major

Aprepitant and Ritonavir: major interaction.

Last updated Sources: US FDA label

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

Ritonavir increases aprepitant exposure substantially. This may increase aprepitant adverse effects such as fatigue, dizziness and elevated liver enzymes.

What this interaction means in plain words

Aprepitant and Ritonavir 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.

Aprepitant belongs to Gastrointestinal Tract; Ritonavir belongs to Anti Virals.

Evidence level: Moderate

Why it happens

Ritonavir is a strong CYP3A4 inhibitor that reduces aprepitant clearance.

What to do

Avoid if possible or use a shorter single-dose aprepitant regimen with monitoring for adverse effects. Consider alternative antiemetics.

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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References

Frequently asked questions

Can I take Aprepitant with Ritonavir?

MediHelp rates the interaction as major. Aprepitant and Ritonavir 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. Ritonavir increases aprepitant exposure substantially. This may increase aprepitant adverse effects such as fatigue, dizziness and elevated liver enzymes.

How serious is the interaction between Aprepitant and Ritonavir?

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 if possible or use a shorter single-dose aprepitant regimen with monitoring for adverse effects. Consider alternative antiemetics.

What other medicines interact with Aprepitant?

MediHelp also lists interactions of Aprepitant with, for example, Lomitapide, Pimozide, Avapritinib. The full list is on the Aprepitant page.

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