NAPLEX (North American Pharmacist Licensure Examination) Practice Exam

Which antibiotic is classified as a protein synthesis inhibitor?

1. Clindamycin

2. Methicillin

3. Ceftriaxone

4. Azithromycin (a Macrolide, also a category under Protein Synthesis Inhibitors but not listed as an answer choice)

The correct answer is: Clindamycin

Clindamycin is classified as a protein synthesis inhibitor because it is able to bind to the 50S subunit of bacterial ribosomes, preventing the formation of peptide bonds and ultimately inhibiting protein synthesis. Other options, such as methicillin and ceftriaxone, target bacterial cell walls and do not directly inhibit protein synthesis. Azithromycin, while also considered a protein synthesis inhibitor in the category of macrolides, was not listed as an answer choice.