What are important considerations and potential complications of management?

A 38-year-old woman presents to the office with complaints of weight loss, fatigue, and insomnia of 3-month duration. She reports that she has been feeling gradually more tired and staying up late at night because she cant sleep. She does not feel that she is doing as well in her occupation as a secretary and states that she has trouble remembering things. She does not go outdoors as much as she used to and cannot recall the last time she went out with friends or enjoyed a social gathering. She feels tired most of the week and states she feels that she wants to go to sleep and frequently does not want to get out of bed. She denies any recent medication, illicit drug, or alcohol use. She feels intense guilt regarding past failed relationships because she perceives them as faults. She states she has never thought of suicide, but has begun to feel increasingly worthless. Her vital signs and general physical examination are normal, although she becomes tearful while talking. Her mental status examination is significant for depressed mood, psychomotor retardation, and difficulty attending to questions. Laboratory studies reveal a normal metabolic panel, normal complete blood count, and normal thyroid functions. What is the most likely diagnosis? What is your next step? What are important considerations and potential complications of management? You need to responded the answer for this case What is the most likely diagnosis? What is your next step? What are important considerations and potential complications of management?