A client with a history of anaphylactic reaction to penicillin receives a prescription for cephalexin 500 mg PO twice daily. Which action should the nurse take?

A. Give with prescribed antihistamine: Administering an antihistamine may help manage mild allergic reactions but does not prevent the risk of a serious, potentially life-threatening anaphylactic reaction. It is unsafe to rely solely on antihistamines when the client has a known severe penicillin allergy and is prescribed a related antibiotic like cephalexin. B. Administer the medication as prescribed: Cephalexin is a cephalosporin, and there is a known cross-sensitivity with penicillins, especially in clients with a history of anaphylaxis. Administering the drug without verifying safety first exposes the client to unnecessary and serious risk. C. Monitor the client for a rash or hives: While monitoring is important after administering any new medication, simply observing for early signs of an allergic reaction is not a proactive or safe strategy when anaphylaxis is a possibility. Prevention of exposure is the priority. D. Contact the healthcare provider (HCP): Clients with a history of anaphylaxis to penicillin are at increased risk for cross-reactivity with cephalosporins. The safest action is to notify the HCP immediately to discuss an alternative antibiotic, avoiding the possibility of a dangerous allergic response.