What are macrolide antibiotics and when are they used?

Macrolides are bacteriostatic antibiotics that work by binding to the 50S ribosomal subunit and inhibiting bacterial protein synthesis. Common macrolides include azithromycin, clarithromycin, and erythromycin. Azithromycin is widely used for community-acquired pneumonia, streptococcal pharyngitis in penicillin-allergic patients, sexually transmitted infections like chlamydia, and skin infections. Macrolides can prolong the QT interval on electrocardiogram, increasing the risk of potentially fatal cardiac arrhythmias.