Final answer:
The nurse should plan to obtain a blood creatinine level test prior to administering the first dose of risperidone for schizophrenia.
Step-by-step explanation:
Prior to administering the first dose of risperidone to manage schizophrenia, the nurse should plan to obtain a blood creatinine level laboratory test. This test is used to assess kidney function, as risperidone is metabolized and eliminated by the kidneys. Monitoring blood creatinine levels helps ensure that the medication is safe and effective for the client.