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Antibiotic interactions: Answers to 4 common questions.
Mary Onysko1, Nathan Holcomb1, Jaime Hornecker1
1University of Wyoming, School of Pharmacy, Laramie, WY, USA.
The Journal of Family Practice
|August 28, 2016
Summary
Certain antibiotics may interact with warfarin, increasing bleeding risk. Some antibiotics also carry a risk of causing drug-induced, prolonged QT intervals, a serious heart rhythm issue.
Area of Science:
- Pharmacology
- Cardiology
- Infectious Diseases
Background:
- Warfarin is a common anticoagulant with a narrow therapeutic index.
- Drug interactions are a significant concern in warfarin management.
- Prolonged QT interval is a risk factor for potentially fatal arrhythmias.
Purpose of the Study:
- To identify antibiotics that interact with warfarin.
- To identify antibiotics associated with QT interval prolongation.
Main Methods:
- Literature review of drug interaction databases.
- Analysis of case reports and clinical studies on antibiotic use in patients on warfarin.
- Review of studies on drug-induced QT prolongation.
Main Results:
- Specific antibiotics, such as macrolides and fluoroquinolones, are frequently implicated in warfarin interactions.
- Several antibiotic classes, including macrolides, fluoroquinolones, and azoles, are associated with QT prolongation.
- The risk of interaction and QT prolongation varies among different antibiotics.
Conclusions:
- Clinicians must carefully consider antibiotic choices in patients taking warfarin.
- Awareness of potential QT interval prolongation is crucial when prescribing antibiotics to all patients.
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