Before starting cephradine (Velosef) for a wound infection, which patient history should be questioned due to potential cross-reactivity?

• A. Penicillin allergy
• B. Hypertension
• C. Drug dependence
• D. Depression

Answer: (A)

Cross-reactivity between penicillins and cephalosporins happens because both are beta-lactam antibiotics with similar structures that the immune system can recognize. Before starting cephradine for a wound infection, it’s important to ask about a history of penicillin allergy because a true penicillin allergy can signal a potential hypersensitivity to cephalosporins. If the patient had a severe penicillin reaction (such as anaphylaxis or significant respiratory involvement), that raises concern about giving cephalosporins and may prompt choosing a different class or proceeding with caution and allergy assessment.

Hypertension, drug dependence, and depression don’t indicate a risk of beta-lactam cross-reactivity, so they aren’t the history that flags potential issues with cephalosporin use.