Drug General Information (ID: DDIHTOXWY5)
  Drug Name Azithromycin Drug Info Ibutilide Drug Info
  Drug Type Small molecule Small molecule
  Therapeutic Class Macrolides Antiarrhythmic Agents
  Structure

 Mechanism of Azithromycin-Ibutilide Interaction (Severity Level: Major)
     Increased risk of prolong QT interval Click to Show/Hide Mechanism Graph
Could Not Find 2D Structure
      Drug Name Azithromycin Ibutilide
      Mechanism Prolong QT interval Prolong QT interval
      Key Mechanism Factor 1
Factor Name QT interval
Factor Description Long QT syndrome is a heart signaling disorder that can cause a fast, chaotic heartbeat (arrhythmia). Many people may not exhibit symptoms, and usually the condition is detected during routine medical tests. In others, the most common symptoms include: sudden fainting, palpitations, dizziness, seizures, sudden death.
      Mechanism Description
  • Increased risk of prolong QT interval by the combination of Azithromycin and Ibutilide 

Recommended Action
      Management The use of macrolide antibiotics in patients receiving class IA or class III antiarrhythmic agents antiarrhythmic agents should generally be avoided unless benefits are anticipated to outweigh the risks. Caution and clinical monitoring are recommended if these agents are prescribed together, especially to patients with underlying risk factors. Patients should be advised to seek medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitations, irregular heartbeat, shortness of breath, or syncope.

References
1 Gitler B, Berger LS, Buffa SD "Torsades de pointes induced by erythromycin." Chest 105 (1994): 368-72. [PMID: 8306730]
2 Lee KL, Jim MH, Tang SC, Tai YT "QT prolongation and torsades de pointes associated with clarithromycin." Am J Med 104 (1998): 395-6. [PMID: 9576415]
3 Product Information. Biaxin (clarithromycin). Abbott Pharmaceutical, Abbott Park, IL.
4 Product Information. ERYC (erythromycin). Parke-Davis, Morris Plains, NJ.
5 Product Information. Erythrocin Lactobionate (erythromycin). Abbott Pharmaceutical, Abbott Park, IL.
6 Product Information. Zithromax (azithromycin). Pfizer US Pharmaceuticals, New York, NY.