Final answer:
The nurse should ask about potential allergies during the Assessment phase of the nursing process to gather essential information and ensure patient safety before proceeding with diagnostic tests like skin testing for allergens.
Step-by-step explanation:
The nurse should ask about a client's potential allergies during the Assessment phase of the nursing process. This is the initial phase where information is gathered about the patient, including medical history, current health status, and any potential allergens that could affect diagnostic testing or treatment procedures. Identifying allergies is crucial to avoid adverse reactions and ensure patient safety, especially before conducting procedures such as skin testing for common allergens.
For example, patients are often instructed to avoid allergy medications prior to testing because these medications could suppress allergic responses, leading to false-negative results. This is why the nurse in a clinic must inquire about allergies during the assessment phase to obtain accurate test results and provide safe, personalized care.