Pharmacy PEBC Practice Exam Flash Cards

PB is a 70 year old female who is on the final day of a 10-day course of cotrimoxazole DS, i po bid for mild pyelonephritis. PB’s medical conditions include hypertension and osteoarthritis, for which she takes enalapril 5 mg po bid and acetaminophen 650 mg po qid. PB has been feeling unwell for the past two days, complaining of abdominal pain, diarrhea, and muscle weakness. She presents to the emergency department, where it is discovered that her serum potassium level is 5.9 mmol/L (normal: 3.5-5.0 mmol/L) and her estimated creatinine clearance is 70 mL/min. What drug therapy problem is PB currently experiencing?