Zosyn is a combination of which two drugs?

• A. Ampicillin and Sulbactam
• B. Piperacillin and Tazobactam
• C. Trimethoprim and Sulfamethoxazole
• D. Ceftriaxone and Metronidazole

Answer: (B)

Zosyn is a combination of piperacillin and tazobactam. Piperacillin is a broad-spectrum penicillin antibiotic effective against a wide range of bacteria, while tazobactam is a beta-lactamase inhibitor. The combination enhances the effectiveness of piperacillin by protecting it from degradation by certain beta-lactamase enzymes produced by resistant bacteria. This synergistic effect makes Zosyn particularly useful in treating a variety of infections, especially those caused by multi-drug resistant organisms.

In the context of other options, while ampicillin and sulbactam (option A) do form a similar combination under the brand name Unasyn, they are distinct from the Zosyn formulation. Trimethoprim and sulfamethoxazole (option C) are both used for treating urinary tract infections and certain bacterial infections, but they work through different mechanisms unrelated to the Zosyn formulation. Lastly, ceftriaxone and metronidazole (option D) are also not involved in the Zosyn composition, as they are entirely different antibiotic classes utilized for various clinical indications.