Ribociclib and Simvastatin: Drug Interaction Guide

Quick answer: This is a major interaction — avoid combining Ribociclib and Simvastatin unless specifically directed by your doctor.

Interaction severity: Major — avoid combination

How Ribociclib interacts with Simvastatin

Ribociclib inhibits CYP3A4, substantially increasing simvastatin exposure and the risk of myopathy and rhabdomyolysis.

What you should do

Avoid combination. Switch to a non-CYP3A4 statin such as pravastatin or rosuvastatin during ribociclib therapy.

Key facts

Severity

Major — avoid combination

Mechanism

Ribociclib inhibits CYP3A4, substantially increasing simvastatin exposure and the risk of myopathy and rhabdomyolysis.

Action

Avoid combination. Switch to a non-CYP3A4 statin such as pravastatin or rosuvastatin during ribociclib therapy.

Important medical disclaimer: This page provides educational information about drug interactions for general reference. It is not a substitute for professional medical advice, diagnosis, or treatment. Always discuss your specific medications with a qualified healthcare provider before starting, stopping, or changing any treatment. About our editorial team.

Frequently asked questions

Can I take Ribociclib and Simvastatin together?

No — this combination should generally be avoided. Avoid combination. Switch to a non-CYP3A4 statin such as pravastatin or rosuvastatin during ribociclib therapy.

What is the severity of this interaction?

The interaction between Ribociclib and Simvastatin is classified as Major — avoid combination. Ribociclib inhibits CYP3A4, substantially increasing simvastatin exposure and the risk of myopathy and rhabdomyolysis.

What should I do if I'm prescribed both?

Avoid combination. Switch to a non-CYP3A4 statin such as pravastatin or rosuvastatin during ribociclib therapy. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

Last reviewed: by iMedic Medical Editorial Team. Our editorial process.