MajorCalcium channel blockers (dihydropyridines)×HMG-CoA reductase inhibitors (statins)
Updated · Methodology
Mechanism
Amlodipine moderately inhibits CYP3A4 – the main simvastatin metabolic route. Simvastatin plasma levels rise by about 77%. Rhabdomyolysis has been reported at simvastatin doses of 40 mg or above.
Symptoms
Pain and weakness in large muscle groups (thighs, shoulders, calves), dark urine, elevated creatine kinase. Severe cases progress to rhabdomyolysis with acute kidney injury. Symptoms appear within 1–4 weeks of co-administration.
Management
Cap simvastatin at 20 mg/day when combined with amlodipine. If LDL targets are missed, switch to pravastatin or rosuvastatin (no CYP3A4 dependence) or replace amlodipine with lisinopril or telmisartan.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.
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Sources
- Lexicomp: Lexicomp Drug Interactions (2024)– Wolters Kluwer Clinical Drug Information, Inc. Lexi-Interact Online, 2024
- FDA: Zocor (simvastatin) prescribing information (2012)
- AEMPS: Ficha técnica: Simvastatina (nº registro 65199), sección 4.5 (2026)– AEMPS, CIMA, nº registro 65199, revisión 03/2026, sección 4.5