Simvastatin and Paritaprevir: 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
Paritaprevir
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.
Let's talk about taking paritaprevir (a hepatitis C medicine) together with simvastatin (a cholesterol medicine like Zocor). Paritaprevir blocks the transporters that normally move simvastatin out of your bloodstream and into your liver. When that happens, simvastatin can build up to much higher levels than intended.
Too much simvastatin can cause serious muscle problems, from aches and weakness to a rare but dangerous breakdown of muscle called rhabdomyolysis. Because of this, these two are considered a combination to avoid together. The good news is your care team has other options, so please talk with your pharmacist or doctor before taking both.
Effect: Increased simvastatin exposure with elevated risk of myopathy and rhabdomyolysis.
Mechanism: Paritaprevir inhibits OATP1B1/OATP1B3-mediated hepatic uptake of simvastatin (an OATP1B1/1B3 substrate), reducing clearance and raising systemic exposure (AUC/Cmax).
- Direction: Increased simvastatin effect and toxicity.
- Severity: Contraindicated.
- Evidence: Theoretical.
- Onset: Unspecified.
Management: Avoid concomitant use. If lipid therapy is needed during paritaprevir-containing regimens, select an alternative statin per prescriber guidance and monitor for muscle symptoms and CK if myopathy is suspected.
What happens
Increased risk of myopathy, including rhabdomyolysis
Interaction Deep Dive
Because paritaprevir inhibits OATP1B1 and OATP1B3, and simvastatin is a substrate of both OATP1B1 and OATP1B3, taking these two drugs together is contraindicated, as it raises the likelihood of myopathy, including rhabdomyolysis1.
Why it happens (mechanism)
Inhibition of OATP1B1 and OATP1B3 efflux transport of simvastatin by paritaprevir
How to manage this interaction
This combination is one your care team will generally want to avoid, so the key step is to keep them informed rather than making changes on your own.
- Don't stop or change either medicine yourself. Talk with your prescriber or pharmacist first.
- Your team may choose a different cholesterol medicine that doesn't interact with paritaprevir.
- Report any muscle pain, tenderness, weakness, or dark urine right away, as these can signal muscle injury.
- Share your full medication list, including your hepatitis C treatment, with every provider.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Simvastatin and Paritaprevir together?
Paritaprevir can raise simvastatin to dangerous levels and increase the risk of serious muscle injury, so this pairing should generally be avoided. Contact your pharmacist or doctor before taking both, and watch for unexplained muscle pain or weakness. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Simvastatin and Paritaprevir 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 Paritaprevir interaction managed?
This combination is one your care team will generally want to avoid, so the key step is to keep them informed rather than making changes on your own. Don't stop or change either medicine yourself. Talk with your prescriber or pharmacist first. Your team may choose a different cholesterol medicine that doesn't interact with paritaprevir. Report any muscle pain, tenderness, weakness, or dark urine r… 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 Paritaprevir 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: VIEKIRA PAK oral tablets, ombitasvir paritaprevir ritonavir oral tablets and dasabuvir oral tablets. AbbVie Inc. (per manufacturer), North Chicago, Il, 2014.
Keep reading about Paritaprevir
Keep reading about Simvastatin
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Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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