Simvastatin and Boceprevir: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 4, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Boceprevir
No brand names on recordSimvastatin
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
These two medicines should not be taken together. Boceprevir (a medicine once used for hepatitis C) blocks the liver enzyme that normally breaks down simvastatin (a cholesterol medicine). When that enzyme is blocked, simvastatin can build up to much higher levels in your body.
Too much simvastatin raises the risk of serious muscle problems, including a rare but dangerous condition called rhabdomyolysis, where muscle tissue breaks down and can harm your kidneys. The good news is that your care team can easily manage this. Please talk with your pharmacist or doctor before taking both, and watch for unexplained muscle pain, tenderness, or weakness.
Contraindicated combination. Boceprevir is a strong CYP3A4 inhibitor; simvastatin is a CYP3A4 substrate (not a prodrug in the sense that would reverse this). Inhibition of CYP3A-mediated simvastatin metabolism increases simvastatin plasma concentrations, raising the risk of myopathy and rhabdomyolysis.
- Direction: increased simvastatin exposure (AUC/Cmax)
- Evidence: theoretical, based on known CYP3A4 mechanism
- Onset: unspecified
- Management: avoid concurrent use. If boceprevir is required, temporarily suspend simvastatin for the duration of therapy. Monitor for muscle pain, weakness, and CK elevation if any overlap occurs.
What happens
Increased simvastatin concentrations and risk of myopathy and rhabdomyolysis
Interaction Deep Dive
Because boceprevir is a potent CYP3A4 inhibitor and simvastatin is a CYP3A4 substrate, giving the two together is contraindicated, since doing so can raise simvastatin plasma levels and heighten the likelihood of serious adverse effects like myopathy, including rhabdomyolysis. Should the combination be necessary, simvastatin should be temporarily withheld for the length of the boceprevir course1.
Why it happens (mechanism)
Inhibition of CYP3A-mediated simvastatin metabolism by boceprevir
How to manage this interaction
This pairing is contraindicated, so the usual approach is to avoid taking them at the same time. Your care team may temporarily suspend simvastatin for the whole time you are on boceprevir, then resume it afterward, or choose a different cholesterol medicine.
- Keep taking your medicines exactly as prescribed until your care team advises a change; do not stop anything on your own.
- Tell your pharmacist or prescriber that you are taking both so they can coordinate the plan.
- Report any unexplained muscle pain, tenderness, weakness, or dark-colored urine right away.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Simvastatin and Boceprevir together?
Boceprevir and simvastatin should not be taken together because boceprevir can raise simvastatin levels and cause serious muscle damage; your care team will typically pause simvastatin during boceprevir treatment or pick another option. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Simvastatin and Boceprevir interaction?
It is rated contraindicated. These should generally not be used together.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Simvastatin and Boceprevir interaction managed?
This pairing is contraindicated, so the usual approach is to avoid taking them at the same time. Your care team may temporarily suspend simvastatin for the whole time you are on boceprevir, then resume it afterward, or choose a different cholesterol medicine. Keep taking your medicines exactly as prescribed until your care team advises a change; do not stop anything on your own. Tell your pharmaci… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Simvastatin or Boceprevir need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (1)
- Product Information: ZOCOR(R) oral tablets, simvastatin oral tablets. Organon & Co (per FDA), Jersey City, NJ, 2022. DailyMed
Keep reading about Boceprevir
Keep reading about Simvastatin
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