Clarithromycin belongs to which antibiotic class?

• A. Macrolides
• B. Cephalosporin
• C. Penicillin
• D. Quinolones

Answer: (A)

The main idea here is recognizing how antibiotics are categorized by their mechanism of action. Clarithromycin is a macrolide antibiotic. Macrolides bind to the 50S ribosomal subunit and block the translocation step in protein synthesis, which stops bacteria from producing essential proteins and slows or halts their growth. This places clarithromycin with other macrolides like erythromycin and azithromycin. In contrast, cephalosporins and penicillins are beta-lactam antibiotics that disrupt cell wall synthesis, and quinolones inhibit DNA gyrase and topoisomerase IV. So the correct classification is macrolides.