Can a patient with a hypersensitivity to cefazolin (Ancef, cefazolin) receive cefepime (Maxipime, cefepime)?

From the Guidelines

Patients with a cefazolin allergy can likely receive cefepime, as the risk of cross-reactivity between these beta-lactam antibiotics is considered low, especially since cefazolin and cefepime have dissimilar side chains 1. The decision to use cefepime in a patient with a cefazolin allergy should be based on the severity and nature of the previous allergic reaction, as well as the specific clinical context. If the patient has a history of a severe or immediate-type hypersensitivity reaction to cefazolin, alternative antibiotics should be considered to minimize the risk of an adverse reaction. However, if the reaction was non-severe or delayed-type, and the patient requires cefepime for a specific infection, the benefits of using cefepime may outweigh the risks, and desensitization protocols or close monitoring may be considered 2. It is essential to note that the risk of cross-reactivity between cephalosporins is generally lower than previously thought, and the side-chain structure of the antibiotic plays a significant role in determining the risk of cross-reactivity 3, 4. In any case, a thorough assessment of the patient's medical history and a careful evaluation of the potential risks and benefits should guide the decision-making process. Key considerations include:

• The severity and nature of the previous allergic reaction to cefazolin
• The specific clinical context and the need for cefepime
• The potential risks and benefits of using cefepime in this patient
• The availability of alternative antibiotics and their potential effectiveness in treating the infection.

From the FDA Drug Label

CONTRAINDICATIONS Cefepime for injection is contraindicated in patients who have shown immediate hypersensitivity reactions to cefepime or the cephalosporin class of antibiotics, penicillins or other beta-lactam antibiotics. WARNINGS Hypersensitivity Reactions to Cefepime, Cephalosporins, Penicillins, or Other Drugs Before therapy with cefepime for injection is instituted, careful inquiry should be made to determine whether the patient has had previous immediate hypersensitivity reactions to cefepime, cephalosporins, penicillins, or other drugs Exercise caution if this product is to be given to penicillin-sensitive patients because cross-hypersensitivity among beta-lactam antibiotics has been clearly documented and may occur in up to 10% of patients with a history of penicillin allergy.

• Hypersensitivity Reactions: The FDA drug label warns of cross-hypersensitivity among beta-lactam antibiotics, which includes cefazolin and cefepime.
• Cefazolin Hypersensitivity: A patient with a hypersensitivity to cefazolin may be at risk of a hypersensitivity reaction to cefepime due to cross-reactivity.
• Precaution: Exercise caution when administering cefepime to a patient with a known hypersensitivity to cefazolin or other beta-lactam antibiotics [5] [6]. The patient should not receive cefepime due to the risk of a hypersensitivity reaction.

From the Research

Cefazolin and Cefepime Cross-Reactivity

• Cefazolin and cefepime are both cephalosporin antibiotics, but they have different R1 side chains 7, 8, 9.
• Studies suggest that patients with a hypersensitivity to cefazolin may not necessarily react to cefepime, as the allergic determinant is often specific to the unique side chain of the antibiotic 7, 10.
• A study found that patients with an IgE-mediated hypersensitivity to penicillins could tolerate cefazolin and ceftibuten, which have side-chain determinants different from those of penicillins 8.

Cefepime Tolerance in Cefazolin-Hypersensitive Patients

• There is limited direct evidence on the tolerance of cefepime in patients with a hypersensitivity to cefazolin 11, 7, 8, 9, 10.
• However, the available data suggest that cefazolin hypersensitivity is often a selective allergy, and patients may tolerate other β-lactam antibiotics, including alternative cephalosporins 10.
• Skin testing and graded drug challenges may be useful in determining the safety of cefepime in patients with a hypersensitivity to cefazolin 8, 10.

Clinical Implications

• Patients with a hypersensitivity to cefazolin should be evaluated on a case-by-case basis to determine the safety of cefepime 7, 8, 9, 10.
• Clinicians should consider the unique side chains of cefazolin and cefepime, as well as the patient's specific allergic reaction, when making decisions about antibiotic use 7, 10.
• Further research is needed to fully understand the cross-reactivity between cefazolin and cefepime, as well as the optimal diagnostic and treatment approaches for patients with hypersensitivity reactions to these antibiotics 9.