1 out of 1 points The anticoagulant drug that acts as a vitamin K antagonist is: Selected Answer: coumadin • Question 2 1 out of 1 points What is a serious side effect of ibuprofen in the older adult patient? Selected Answer: Impairment of renal function • Question 3 1 out of 1 points A Nurse Practitioner is conducting an assessment of a patient who has recently had several changes made to her drug regimen. What assessment question most directly addresses the safety implications of the patient's drug regimen? Selected Answer: "Do you take any herbal supplements or alternative medications?" • Question 4 1 out of 1 points Which can elevate theophylline levels? Selected Answer: Concomitant treatment with cimetidine (Tagamet)..