What additional drug allergy should a nurse assess for before administering cephalexin monohydrate?

Cephalexin monohydrate belongs to the class of cephalosporins, which are structurally related to penicillins. A significant cross-reactivity exists between penicillins and cephalosporins; therefore, a history of penicillin allergy is particularly important to assess. Patients who are allergic to penicillin may also experience allergic reactions when administered cephalexin.

This aspect is critical in clinical settings as allergic reactions can range from mild skin rashes to severe anaphylaxis. Knowing a patient’s history of penicillin allergy helps the nurse take appropriate precautions and select alternative antibiotics if necessary.

While allergies to aminoglycosides, erythromycins, and sulfonamides are also worth noting, they do not have the same well-documented cross-reactivity with cephalexin as penicillins do.