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Updated: Apr 19, 2026

Multiplex Therapeutic Drug Monitoring by Isotope-dilution HPLC-MS/MS of Antibiotics in Critical Illnesses
Published on: August 30, 2018
Cardiac risks associated with antibiotics: azithromycin and levofloxacin.
Zhiqiang Kevin Lu1, Jing Yuan, Minghui Li
1University of South Carolina, South Carolina College of Pharmacy, Clinical Pharmacy and Outcomes Sciences Department , 715 Sumter Street, CLS Building, Room 311G, Columbia, SC 29208 , USA +1 803 777 2653 ; +1 803 777 2820 ; luk@sccp.sc.edu.
Azithromycin and levofloxacin, while effective antibiotics, carry rare risks of QT prolongation. Cardiovascular death risks are debated, necessitating careful consideration of benefits versus potential harms.
Area of Science:
- Pharmacology and Therapeutics
- Cardiovascular Risk Assessment
- Infectious Disease Management
Background:
- Azithromycin and levofloxacin are commonly used antibiotics with established efficacy.
- Previously considered rare, potential adverse drug events include QT prolongation, as warned by the US FDA.
- Understanding the cardiovascular risks associated with these antibiotics is crucial for patient safety.
Purpose of the Study:
- To critically review existing literature on the cardiovascular risks of azithromycin and levofloxacin.
- To synthesize findings from various study designs, including case reports, observational studies, and clinical trials.
- To inform clinical decision-making regarding the use of these antibiotics.
Main Methods:
- Systematic review of 15 case reports/series, 5 observational studies, and 5 clinical trials.
- Focus on studies assessing cardiovascular risks, specifically QT prolongation and cardiovascular death.
- Critical appraisal of evidence to evaluate the association between antibiotic use and cardiac events.
Main Results:
- Conflicting evidence exists regarding the cardiovascular risks of azithromycin.
- Some studies suggest an increased risk of cardiovascular death with azithromycin compared to amoxicillin, while others show no difference.
- Limited evidence suggests a potential increased risk of cardiovascular death with levofloxacin in one retrospective study.
Conclusions:
- The risk-benefit profile of azithromycin and levofloxacin requires careful consideration in clinical practice.
- While potential risks exist, these antibiotics may still be prescribed when indicated, provided risks are understood.
- Further research may be needed to clarify the definitive cardiovascular risks associated with these widely used antibiotics.
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