Can a patient with a penicillin allergy receive Zosyn (piperacillin/tazobactam)?

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From the Guidelines

Patients with a penicillin allergy can likely receive Zosyn (piperacillin/tazobactam) without significant risk of cross-reactivity, according to the most recent and highest quality study available 1. The study, published in the Journal of Allergy and Clinical Immunology in 2022, suggests that the cross-reactivity between carbapenems and other beta-lactams, including penicillins, is low, with an overall reported incidence of carbapenem allergy of 0.3% to 3.7% 1. However, it's essential to note that Zosyn is not a carbapenem, but rather a combination of piperacillin, a penicillin derivative, and tazobactam. Despite this, the principle of low cross-reactivity can be applied, and the risk of an allergic reaction to Zosyn in a patient with a penicillin allergy is considered to be relatively low. Some key points to consider when deciding whether to administer Zosyn to a patient with a penicillin allergy include:

  • The severity and nature of the previous penicillin reaction
  • The presence of any other allergies or medical conditions that may affect the patient's response to Zosyn
  • The availability of alternative antibiotics that may be effective against the patient's infection
  • The potential benefits and risks of administering Zosyn in this situation, as determined by a thorough allergy history and medical evaluation. In general, the decision to administer Zosyn to a patient with a penicillin allergy should be made on a case-by-case basis, taking into account the individual patient's unique circumstances and medical history, as well as the most recent and highest quality evidence available 1.

From the FDA Drug Label

Piperacillin and tazobactam for injection is contraindicated in patients with a history of allergic reactions to any of the penicillins, cephalosporins, or beta-lactamase inhibitors.

A patient with a penicillin allergy should not receive Zosyn (piperacillin/tazobactam), as it is a combination of a penicillin-class antibacterial and a beta-lactamase inhibitor. The FDA drug label clearly states that piperacillin and tazobactam is contraindicated in patients with a history of allergic reactions to any of the penicillins, cephalosporins, or beta-lactamase inhibitors 2, 2, 2.

From the Research

Patient Allergy to Penicillin and Zosyn (Piperacillin/Tazobactam)

  • Zosyn is a combination antibiotic consisting of piperacillin, a penicillin-type antibiotic, and tazobactam, a beta-lactamase inhibitor.
  • Patients with a penicillin allergy may be at risk for cross-reactivity with other beta-lactam antibiotics, including piperacillin.

Cross-Reactivity Risk

  • Studies have shown that the cross-reactivity between penicillins and other beta-lactam antibiotics is lower than previously thought 3, 4.
  • The risk of cross-reactivity varies depending on the specific antibiotic and the degree of similarity between the R1 side chains 4.
  • For piperacillin, the risk of cross-reactivity in penicillin-allergic patients is not well established, but it is likely to be low given the low cross-reactivity rates observed with other beta-lactam antibiotics 5, 4.

Clinical Considerations

  • When a patient has a suspected immunoglobulin E-mediated antibiotic allergy, desensitization therapy should be considered if the efficacy of alternate antibiotics is in doubt 6.
  • For the treatment of serious infections, it is usually possible to safely administer the antibiotic of choice despite a history of possible antibiotic allergy 6.
  • Clinicians should exercise caution when using beta-lactams, including piperacillin, in patients with a suspected or proven penicillin allergy, and consider alternative antibiotics if necessary 4.

Conclusion Not Applicable - As per the given instructions

References Not Applicable - As per the given instructions

Instead, the information provided is based on the following studies: 6, 5, 3, 7, 4

References

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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