Which monitoring is recommended after starting an ACE inhibitor?

• A. Regular liver function tests
• B. Weekly chest X-ray
• C. Check kidney function in the first week
• D. Monitor for decreased potassium levels

Answer: (C)

When you start an ACE inhibitor, the body’s kidney dynamics can change quickly because these drugs dilate the efferent arterioles of the glomerulus, which can lower filtration pressure. That means the kidney’s function can dip early on, especially in people with existing kidney disease, dehydration, or renal artery stenosis. Checking kidney function in the first week after initiating therapy helps catch any early decline in GFR or rise in creatinine, so you can adjust the dose or stop the medication if needed to prevent further kidney injury.

It’s also important to monitor potassium, because ACE inhibitors can raise potassium levels (hyperkalemia) rather than decrease them. The other options aren’t routinely needed: liver function tests aren’t specifically required for ACE inhibitors, and weekly chest X-rays aren’t part of standard monitoring. The key protective step after starting an ACE inhibitor is an early check of kidney function.