From the Guidelines
Zosyn (piperacillin-tazobactam) should not be given to patients with a known severe penicillin allergy due to the risk of cross-reactivity and potential severe allergic reactions, as recommended by the most recent guidelines 1. When considering the administration of Zosyn to a patient with a penicillin allergy, it is crucial to assess the severity of the allergy.
- For patients with a history of severe reactions such as anaphylaxis, angioedema, or Stevens-Johnson syndrome, alternative antibiotics should be used to avoid potentially life-threatening reactions.
- The Dutch Working Party on Antibiotic Policy (SWAB) guideline 1 suggests that patients with a suspected non-severe, immediate-type allergy to a cephalosporin can receive penicillins with dissimilar side chains, but this does not directly apply to Zosyn, which is a penicillin derivative.
- The guideline also recommends that any carbapenem can be used in patients with suspected immediate-type allergy to a cephalosporin, which might be a safer alternative for patients with severe penicillin allergies.
- However, for patients with mild penicillin allergies, such as a minor rash, Zosyn administration might be considered after careful risk assessment, possibly with close monitoring or desensitization protocols in specialized settings, as suggested by the guideline's approach to non-severe allergies 1.
- It is essential to consult with an infectious disease specialist or allergist to determine the safest approach for patients with penicillin allergies who require antimicrobial therapy, especially when considering the use of Zosyn or other beta-lactam antibiotics 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. Patients with a history of allergic reactions to any of the penicillins, cephalosporins, or beta-lactamase inhibitors.
No, we cannot give Zosyn (piperacillin and tazobactam) to a patient allergic to penicillin, as it is a penicillin-class antibacterial and is contraindicated in patients with a history of allergic reactions to any of the penicillins, cephalosporins, or beta-lactamase inhibitors 2 2.
From the Research
Zosyn Administration in Penicillin-Allergic Patients
- Zosyn, also known as piperacillin-tazobactam, is a beta-lactam antibiotic that may be considered for patients with a reported penicillin allergy 3, 4.
- However, the decision to administer Zosyn to a penicillin-allergic patient should be made with caution, as cross-reactivity between penicillin and other beta-lactams can occur, although it is less common than previously thought 5, 6.
- The risk of cross-reactivity to cephalosporins and carbapenems in penicillin-allergic patients varies, with a higher risk associated with aminocephalosporins and a lower risk with low-similarity-score cephalosporins and carbapenems 5.
Evaluation of Penicillin Allergy
- A thorough evaluation of the patient's allergy history is essential to determine the risk of an allergic reaction to Zosyn 3, 7.
- Patients with a low-risk allergy history, such as isolated nonallergic symptoms or a family history of penicillin allergy, may be able to tolerate Zosyn 3.
- Patients with a moderate-risk history, such as urticaria or other pruritic rashes, may require further evaluation, such as penicillin skin testing, to determine their risk of an allergic reaction 3.
- Patients with a high-risk history, such as anaphylaxis or positive penicillin skin testing, should avoid Zosyn and other beta-lactam antibiotics 3, 7.
Management of Penicillin Allergy
- Clinicians should consider the patient's individual risk factors and medical history when deciding whether to administer Zosyn to a penicillin-allergic patient 7, 4.
- Desensitization may be an option for patients who require treatment with Zosyn and have a confirmed penicillin allergy 7.
- Pharmacists play an essential role in inquiring about patient-specific reactions to presumed medication allergies and developing a further assessment plan, if needed, to determine if the medication allergy is real 4.