An RN, short for Registered Nurse, works closely with doctors to provide patient care for illnesses and injuries. RNs are often the first medical professional the patient sees when entering a health care facility. As an RN, you can ask the patient questions and document their health history, but you are not allowed to diagnose patients; after the doctor or other supervising health care professional has determined what problem needs to be treated, you help administer treatment. Your job duties may include administering medications, checking patient vital signs, and charting medical records. RNs also advise patients and families about at-home care for medical conditions as well as disease prevention.