Captopril Renogram (Renal Scan) at Swedish

Information and Preparation Instructions

The purpose of this exam is to look for renal artery stenosis, obstruction, or trauma. You will be admitted to the Acute Care Unit prior to exam, where you will be given oral Captopril (an ACE (angiotensin-converting enzyme) inhibitor). Your vital signs will be monitored every 15 minutes. At 1 hour, you will be brought to the Radiology department. The technologist will inject a radioactive tracer through the intravenous (I.V.) line and images begin immediately. The radiotracer will not cause any allergic reaction or discomfort. At 20 minutes, the technologist will administer a diuretic (Lasix) to flush out the kidneys (unless otherwise requested by the physician). Images will continue for 20 more minutes or until you can no longer tolerate a full bladder. (A repeat exam is sometimes necessary without giving Captopril).

Before Your Captopril Renogram (Renal Scan)

  • ACE inhibitors must be discontinued 3 days prior to exam
  • Discontinue any diuretics 3 days prior to exam
  • Drink 500 mL or 16 oz. of fluid prior to the exam
  • No food 4 hours prior to exam