Does Zosyn (piperacillin/tazobactam) have anaerobic coverage?

From the Guidelines

Yes, Zosyn (piperacillin-tazobactam) provides excellent coverage against anaerobic bacteria. This combination antibiotic contains piperacillin, an extended-spectrum penicillin, and tazobactam, a beta-lactamase inhibitor. Zosyn effectively treats infections caused by anaerobic organisms including Bacteroides fragilis, Bacteroides species, Clostridium species, Peptostreptococcus species, and Fusobacterium species. The typical adult dosage is 3.375g or 4.5g IV every 6-8 hours, with adjustments needed for renal impairment. Zosyn's mechanism of action involves piperacillin binding to penicillin-binding proteins to inhibit bacterial cell wall synthesis, while tazobactam protects piperacillin from degradation by beta-lactamase enzymes that many anaerobes produce. This broad-spectrum coverage makes Zosyn particularly useful for intra-abdominal infections, complicated skin infections, and other polymicrobial infections where anaerobes are likely to be present alongside aerobic bacteria, as supported by the 2017 guidelines for management of intra-abdominal infections 1. Some key points to consider when using Zosyn include:

• Its effectiveness against a wide range of anaerobic organisms
• The importance of adjusting the dosage for renal impairment
• The potential for Zosyn to be used in combination with other antibiotics for certain types of infections
• The need to consider local resistance patterns and the individual patient's risk factors for resistant pathogens when selecting empiric antibiotic therapy, as recommended by the 2017 guidelines 1. In terms of specific evidence, the 2017 guidelines for management of intra-abdominal infections note that beta-lactam/beta-lactamase inhibitor combinations, such as piperacillin/tazobactam, have in vitro activity against gram-positive, gram-negative, and anaerobe organisms, making them a viable option for the management of severe IAIs 1. However, it is also important to consider the potential risks and limitations of using Zosyn, including the risk of resistance and the need for careful selection of patients and dosing regimens. Overall, Zosyn is a valuable option for the treatment of infections caused by anaerobic bacteria, and its use should be guided by careful consideration of the individual patient's needs and the latest available evidence.

From the FDA Drug Label

Piperacillin and tazobactam has been shown to be active against most isolates of the following microorganisms, both in vitro and in clinical infections [see Indications and Usage (1)] Anaerobic bacteria Bacteroides fragilis group (B. fragilis, B. ovatus, B. thetaiotaomicron, and B. vulgatus)

Yes, Zosyn (piperacillin/tazobactam) has anaerobic coverage against certain bacteria, including Bacteroides fragilis group 2.

From the Research

Zosyn Anaerobic Coverage

• Zosyn, also known as piperacillin/tazobactam, has a broad spectrum of antibacterial activity that includes Gram-positive and Gram-negative aerobic and anaerobic bacteria 3.
• The combination of piperacillin and tazobactam provides coverage against many pathogens producing beta-lactamases, including anaerobic bacteria 3, 4.
• Studies have shown that piperacillin/tazobactam is effective in treating infections caused by anaerobic bacteria, including intra-abdominal, skin and skin structure, and acute pelvic infections 5.
• The efficacy of piperacillin/tazobactam against anaerobic bacteria is comparable to other antibiotics, such as ertapenem, in the treatment of mixed anaerobic infections 5.
• Piperacillin/tazobactam has been shown to be effective against a wide range of anaerobic bacteria, including Bacteroides fragilis group and peptostreptococci 5, 4.

Specific Anaerobic Coverage

• Bacteroides fragilis group: piperacillin/tazobactam has been shown to be effective against this group of anaerobic bacteria 5, 4.
• Peptostreptococci: piperacillin/tazobactam has been shown to be effective against this group of anaerobic bacteria 5.
• Other anaerobic bacteria: piperacillin/tazobactam has a broad spectrum of activity that includes many other anaerobic bacteria, although specific data on efficacy against these organisms may be limited 3, 4.