This is a test which can show how well the kidneys are functioning, thereby identifying the presence of kidney disease.  For this test a small amount of a radioactive compound is injected into your vein. This compound is excreted by the kidneys into the urine. A specialised camera is then used to take pictures (scans) of your kidneys.

How to Prepare?

If a Captopril renal study is required, you may be asked by your doctor to stop taking ACEinhibitors

(e.g. Capoten, Renitec) for several days before the scan. Otherwise, take all of your usual medications.

You should fast for 4 hours prior to the scan if you are having a Captopril Study. Otherwise, there is no need to fast for the test. You should drink plentiful fluids prior to the test.

The test is usually not performed in pregnant women, so if you know that you are (or think you might be) pregnant, please inform us before the test begins.

What to Expect?

After the test is explained to you, a needle will be placed into a vein in your arm (usually near the elbow) and a radioactive compound will be administered. Images are taken for about 45 minutes.

A diuretic (lasix) may be administered intravenously to assess washout from the renal tracts to look for obstructions.

There are no side effects or reaction from the injection. The injection does NOT contain iodine and is therefore safe in people who are allergic to radiological contrast injections. Although you will be required to keep still during the scan, the procedure itself is completely painless. There is no need to hold your breath during the test.


In general, the scans and results are sent to your doctor the next working day. Depending on the type of scan you are having (and the clinical urgency), you may be able to take the scan with you in some cases, however there will be a delay while the report is typed.

You can drive home after the scan. You will not be drowsy in any way.

Please remember to bring your requesting letter and any recent X-rays or CT scans. At the time of your appointment, report to North Shore Radiology and Nuclear Medicine, which is located on the ground floor of North Shore Private Hospital in Westbourne St.

If you have any questions please phone North Shore Radiology and Nuclear Medicine on 8425 3684. We will be happy to answer any queries that you may have.

Additional Information