What is a Captopril Renal Scan?

This test is for patients who have moderate to high risk renovascular hypertension.

How should I prepare for a Captopril Renal Scan?

You should not have anything to eat for 4 hours prior to this test. You can have water only. Before scheduling someone will contact you about all medications you are taking because there are several medications that have to be held for this study.

How long does the test take?

This test takes approximately 3 hours to perform.

When you arrive to the nuclear medicine department we will first go over all medications that you are taking, so it may be helpful to have a list of your medications and when you last took them. You will then be instructed to consume water orally. The calculation of water is based on weight. After you are finished drinking the water an intravenous catheter will be placed in your arm. An injection of a radioactive isotope will be given through your IV and continuous 30 minute images will be taken of your kidneys. There are no side effects to this injection. After the 30 minutes of imaging you will then be asked to drink more water and also consume 25mg of Captopril orally. Captopril is and ACE inhibitor. Blood pressures will then be taken for one hour. You will next be asked to empty your bladder and the technologist will give you another injection of the radioactive isotope and another 30 minute scan will be taken.

How soon will the scan results be available?

Immediately after the images are taken, the technologist will print them and have the doctor mark the sentinel node.

It is essential to tell your doctor if you are pregnant or think you might be pregnant before undergoing this scan because of radiation exposure.

Reviewed by a Cleveland Clinic medical professional.

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