Pathophysiology

Please answer the question succinctly and keep responses under 2000 characters. Please provide a listing of websites or other references you used to answer each question at the END of the document

A 36-year-old woman, who has been taking aspirin for back pain, experiences a sudden sense of chest discomfort and feeling faint that is accompanied by the vomiting of coffee-ground emesis and the passing of tarry stool. She relates that she has not had any signs of stomach disorders like pain or heartburn prior to this episode.
1.What is this patients most likely diagnosis?
2.Based upon your diagnosis, why would this patient not have experienced symptoms prior to this episode?
3.Do some research and explain why NSAIDs like aspirin degrade the mucosal layer of the stomach (be specific and relate NSAIDs mechanisms of action!!!).