Clarithromycin and Amlodipine: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Clarithromycin
Amlodipine
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 risk of hypotension, acute kidney injury, bradyarrhythmias, lactic acidosis and peripheral edema
Interaction Deep Dive
Coadministration of clarithromycin (a strong CYP3A4 inhibitor) and calcium channel blockers (CCBs) metabolized by CYP3A4 has resulted in serious adverse effects including hypotension and acute kidney injury23. Additionally, concomitant administration may also cause bradyarrhythmias, lactic acidosis, and peripheral edema 3. Use caution with concomitant administration of clarithromycin and calcium channel blockers metabolized by CYP3A4 23. If clinically appropriate, consider the use of azithromycin (which does not inhibit CYP3A4) if treatment with a macrolide is required 1.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism by clarithromycin
Literature reports
3 reports — tap to read
a) Coadministration of macrolide antibiotics erythromycin or clarithromycin with a calcium channel blocker was associated with significantly increased short-term risk of hospital admission within 7 days for hypotension or shock ([OR, 5.8; 95% CI, 2.25 to 14.98] or [OR, 3.7; 95% CI, 2.26 to 6.06]) in a case-crossover cohort study of geriatric patients (N=7100); there was no significant risk associated with azithromycin. In a stratified analysis of dihydropyridine calcium channel blockers (amLODIPine, felodipine, NIFEdipine), the results remained significant for coadministration of erythromycin or clarithromycin. Calcium channel blocker treatment included dilTIAZem (40%), amLODIPine (29.6%), NIFEdipine (19.4%), verapamil (8%), or felodipine (3%). The findings suggest that erythromycin and clarithromycin potentiate calcium channel blockers (CYP3A4 substrates) by inhibiting CYP3A4; azithromycin does not inhibit CYP3A4 1.
b) 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 4.
c) In elderly hypertensive patients, coadministration of amLODIPine 5 mg with dilTIAZem (a moderate CYP3A4 inhibitor) 180 mg daily resulted in a 60% increase in amlodipine exposure 5.
Common questions
Can I take Clarithromycin and Amlodipine together?
Increased risk of hypotension, acute kidney injury, bradyarrhythmias, lactic acidosis and peripheral edema Always confirm with your pharmacist or prescriber before making any change.
How serious is the Clarithromycin and Amlodipine interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
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 Clarithromycin or Amlodipine 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 (5)
- Wright AJ, Gomes T, Mamdani MM, et al: The risk of hypotension following co-prescription of macrolide antibiotics and calcium-channel blockers. CMAJ 2011; 183(3):303-307. PubMed
- Product Information: BIAXIN(R) XL Filmtab(R) oral extended-release tablets, clarithromycin oral extended-release tablets. AbbVie Inc (per FDA), North Chicago, IL, 2018. DailyMed
- Product Information: VOQUEZNA(TM) TRIPLE PAK(TM) oral kit, vonoprazan oral tablets, amoxicillin oral capsules, clarithromycin oral tablets kit. Phathom Pharmaceuticals (per FDA), Buffalo Grove, IL, 2023. 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
- Product Information: NORVASC(R) oral tablets, amlodipine besylate oral tablets. Pfizer Labs (per FDA), New York, NY, 2013. DailyMed
Keep reading about Clarithromycin
Keep reading about Amlodipine
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