Nimodipine and Clarithromycin: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Clarithromycin
Nimodipine
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
Increased nimodipine exposure and risk of significant hypotension
Interaction Deep Dive
Concomitant use of clarithromycin and nimodipine is contraindicated. Use of nimodipine, a CYP3A4 substrate, and clarithromycin, a strong CYP3A4 inhibitor, may increase nimodipine exposure and cause significant hypotension.1. A small but significant 30-day increased risk of hospitalization with acute kidney injury was observed in patients who received continuous calcium channel blocker therapy and were prescribed clarithromycin in a retrospective cohort of older adults (mean age, 76 years) 2.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated nimodipine metabolism by clarithromycin
Literature reports
1 report — tap to read
a) Relative to azithromycin, clarithromycin was associated with a small but significant 30-day increased risk of hospitalization with acute kidney injury (HAKI) in patients who received continuous calcium channel blocker (CCB) therapy in a retrospective cohort of older adults (mean age, 76 years). Of the patients receiving clarithromycin, CCB usage included: amlodipine (52.7%), diltiazem (22.2%), nifedipine (17.3%), verapamil (4%), or felodipine (3.8%). The median dose of clarithromycin was 1000 mg/day for 10 days (n=96,226) and the median dose of azithromycin was 300 mg/day for 5 days (n=94,083). Pooled data was analyzed, 30 days after the antibiotic was prescribed, for diagnostic code of HAKI (median absolute acute increase in serum creatinine of 1.11 mg/dL). HAKI occurred in 0.44% of patients prescribed clarithromycin compared with 0.22% of patients prescribed azithromycin (odds ratio [OR], 1.98; 95% CI, 1.68 to 2.34; number needed to harm (NNH), 464). Relative to amlodipine (reference), the risk of HAKI was highest with nifedipine, followed by felodipine, diltiazem, and verapamil. Similarly, concomitant use of clarithromycin in CCB recipients was associated with a small but significant 30-day increased risk of hospitalization with hypotension (absolute risk increase, 0.04%) and all-cause mortality (absolute risk increase, 0.43%). Risk of HAKI appeared unaffected by presence of chronic kidney disease (CKD) or statin use; however, NNH decreased to 95 in those with CKD. Additional multiple analyses showed similar results, suggesting robustness of findings 2.
Common questions
Can I take Nimodipine and Clarithromycin together?
Increased nimodipine exposure and risk of significant hypotension Always confirm with your pharmacist or prescriber before making any change.
How serious is the Nimodipine and Clarithromycin interaction?
It is rated contraindicated. These should generally not be used together.
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 "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 Nimodipine or Clarithromycin 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 (2)
- Product Information: nimodipine oral capsules, nimodipine oral capsules. Caraco Pharmaceutical Laboratories, Ltd. (per DailyMed), Detroit, MI, 2012. DailyMed
- Gandhi S, Fleet JL, Bailey DG, et al: Calcium-channel blocker–clarithromycin drug interactions and acute kidney injury. JAMA 2013; 310(23):2544-2553. PubMed
Keep reading about Clarithromycin
Keep reading about Nimodipine
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.
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