As a medical professional with expertise in pharmacology, I can provide you with information on antibiotics that are known to potentially prolong the QT interval, which is the time between the start of the Q wave and the end of the T wave in the heart's electrical cycle as measured on an electrocardiogram (ECG). Prolongation of the QT interval can lead to serious, potentially fatal, heart rhythm disturbances. Antioxidants that are known to increase the QT interval include, but are not limited to: 1. Macrolide antibiotics: Erythromycin, clarithromycin, and azithromycin. 2. Fluoroquinolones: Levofloxacin, moxifloxacin, and ciprofloxacin. 3. Tetracyclines: Doxycycline and minocycline. 4. Aminoglycosides: Gentamicin and tobramycin. 5. Antimalarials: Halofantrine and chloroquine. 6. Linezolid: An oxazolidinone antibiotic. 7. Penicillins: Some, like piperacillin/tazobactam, have been reported to cause QT prolongation. It's important to note that not all antibiotics in these classes will necessarily cause QT prolongation, and the risk can vary among individuals. Other factors, such as liver or kidney function, concomitant medications, and underlying health conditions, can also affect the risk. read more >>

Macrolides such as clarithromycin and erythromycin have been associated with QT prolongation and TdP [Lee et al. 1998; Ray et al. 2004]. In animal studies, erythromycin was found to have similar effects to class III antiarrhythmic agents with prolongation of QT interval, induction of EAD and transmural dispersion.read more >>