A nurse is reinforcing teaching with a newly licensed nurse about monitoring morphine patient-controlled analgesia (PCA). Which of the following information should the nurse include?

"Instruct the client's visitors not to operate the PCA pump.”

"Check the client's pain level every 8 hours."

"Diarrhea is an adverse effect of morphine PCA.”

"Using morphine PCA increases the client's risk of toxicity."