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QT Interval Prolongation Associated with Azithromycin/Methadone Combination

S Amer1, S Hassan2, M Shariffi2

  • 1Henry For Hospital, Detroit, Michigan, USA. drsyedamer1@gmail.com.

The West Indian Medical Journal
|August 14, 2014
PubMed

Insights

A man on methadone experienced QT prolongation when treated with azithromycin for pneumonia. This case reveals a new drug interaction, urging caution when combining azithromycin with drugs known to prolong the QT interval.

Area of Science:

  • Pharmacology
  • Clinical Medicine
  • Cardiology

Background:

  • Methadone is commonly used for opioid replacement therapy.
  • Azithromycin is a widely prescribed antibiotic for community-acquired pneumonia.
  • QT prolongation is a cardiac condition that can lead to dangerous arrhythmias.

Purpose of the Study:

  • To report a novel drug interaction between methadone and azithromycin.
  • To highlight the risk of QT prolongation in patients on methadone therapy.
  • To emphasize the importance of cautious azithromycin use in patients with risk factors for arrhythmias.

Main Methods:

  • Case report documentation.
  • Review of patient's medical history and medication regimen.
  • Analysis of cardiac monitoring data.

Main Results:

  • A 57-year-old male patient on methadone replacement therapy developed QT prolongation.
  • The event occurred during treatment with azithromycin for community-acquired pneumonia.
  • This suggests a potential drug-drug interaction between methadone and azithromycin.

Conclusions:

  • Azithromycin may interact with methadone, leading to QT prolongation.
  • Healthcare providers should exercise caution when prescribing azithromycin to patients on methadone.
  • Monitoring for QT interval changes is crucial in patients receiving both medications.

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