Mibefradil and Atorvastatin: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Jul 15, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Atorvastatin
Mibefradil
No brand names on record
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.
What happens
An increased risk of myopathy and/or rhabdomyolysis
Interaction Deep Dive
Rhabdomyolysis and myopathy have been observed in patients treated with some HMG-CoA reductase inhibitors and mibefradil. Atorvastatin is metabolized by CYP450 3A4 to active and inactive metabolites, so the overall effect of mibefradil, a potent inhibitor of CYP450 3A4, on atorvastatin may not be large. However, until more definitive information is available, the concurrent administration of atorvastatin and mibefradil should be avoided1.
Why it happens (mechanism)
Inhibition of atorvastatin metabolism
Common questions
Can I take Mibefradil and Atorvastatin together?
An increased risk of myopathy and/or rhabdomyolysis Always confirm with your pharmacist or prescriber before making any change.
How serious is the Mibefradil and Atorvastatin interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "delayed". Effects tend to build up gradually over days to weeks.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Mibefradil or Atorvastatin 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: Posicor(R), mibefradil dihydrochloride. Roche Laboratories Inc. Nutley, NJ, 1997.
Keep reading about Atorvastatin
Keep reading about Mibefradil
These medications also interact with supplements
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.
Check another combination
Our instant two-drug interaction checker is almost here.
Still have questions about this combination?
Every question gets a real answer from a licensed pharmacist — free, and usually within a day.
Ask the pharmacist