Snapshot A 67-year-old Caucasian man presents to his primary care physician for follow-up of his hypertension. He was recently started on a lisinopril for chronic hypertension. He has been monitoring his blood pressure at home and they have all been within the normal range. However, he reports a new cough that began a few days after starting lisinopril. Introduction Mechanism of action inhibits angiotensin-converting enzyme (ACE) ↓ angiotensin II (AT II) recall that AT II increases blood pressure by constricting renal and peripheral vasculature and increasing sodium reasorption in the kidney ↓ AT II prevents constriction of efferent arterioles and ↓ glomerular filtration rate (GFR) ↓ negative feedback and ↑ renin ↑ bradykinin, a potent vasodilator ACE normally degrades/inactivates bradykinin Clinical use hypertension myocardial infarction prevents heart remodeling heart failure (this medication decreases mortality) proteinuria diabetic nephropathy Toxicity cough angioedema due to ↑ bradykinin contraindicated in patients with C1 esterase inhibitor deficiency teratogenic effects on fetuses disrupts fetal renal development contraindicated in pregnant woman ↑ creatinine (↓ GFR) contraindicated in bilateral renal artery stenosis because ACE inhibitors may further ↓ GFR and cause renal failure hyperkalemia hyponatremia metabolic acidosis hypotension Medications captopril lisinopril enalapril ramipril