Common antibiotics may disrupt heart rhythm, expert warns

Cardiologist Dr. Denis Sokolov has warned that certain antibiotics from the macrolide class, such as azithromycin and clarithromycin, may affect the heart's electrical activity, particularly in patients with existing heart rhythm disorders.

Sokolov explained that taking these antibiotics without medical supervision, or in combination with other medications, can inhibit potassium channels in heart cells. This impacts the repolarization process and prolongs the QT interval on an electrocardiogram.

He noted that the QT interval represents the time between the start of the Q wave and the end of the T wave, reflecting the period of depolarization and repolarization in the heart's ventricles. Prolongation of this interval may increase the risk of developing arrhythmias.

Sokolov added that the risk rises if the patient is also taking other drugs that affect heart rhythm, such as certain antiarrhythmics and antidepressants, as the negative effects of these medications can be amplified when used together.