A 20-year-old female college student presents due to a 7-day history of daily heartburn. She has never experienced heartburn as bad as she does currently. She is treating this with over-the-counter histamine-2 receptor antagonist, famotidine, 1 tablet daily. The patient denies any other significant past medical history and is currently taking a daily multivitamin and an antihistamine for seasonal allergies. She recently admits to having increased episodes of headaches that she believes are due to stress. For this reason, she has been taking ibuprofen 600 mg every 8 hours. She states that she has been taking this consistently every 8 hours for the last 10 days; she hopes that after finals are finished, her headaches will subside. She also states that she was given amoxicillin 2 weeks ago for a middle ear infection, which resolved without any further intervention. She denies any difficulty swallowing, weight loss, night sweats, chest pain, black tarry stool, use of tobacco/alcohol, or coughing up blood. Physical examination is unremarkable for any abnormalities.
Which of the following medications that the patient mentioned is most likely causing her increased gastrointestinal symptoms?
A) Antibiotic
B) H2-receptor antagonist
C) Multivitamin
D) H1-receptor antagonist
E) NSAID
