Nancy has a new diagnosis of panic disorder. Dr. S has writt…

Nancy has a new diagnosis of panic disorder. Dr. S has written a prn order for Alprazolam (Xanax) for when Nancy is feeling anxious. She says to the nurse, “Dr. S prescribed Buspirone (Buspar) for my friend’s anxiety. Why did he order something different for me?” The nurse’s answer is based on which of the following?