This webpage explains more about having a renogram including the benefits, risks and any alternatives. It also provides information on what you can expect when you come to hospital.
If you have any further questions, please speak to your doctor, nuclear medicine radiographer or nurse.
A renogram is a nuclear medicine test of the kidneys. It can be used to see how well each kidney is working and whether urine passes on into the bladder without obstruction.
For this test it is necessary to inject a small amount of radioactive tracer, called a radiopharmaceutical, in order to take the pictures. The radioactive dose you receive from this scan is small (similar to a CT scan) and the associated risks are minimal. The radiology staff are responsible for making sure that your dose is kept as low as practicable and that the benefits of having the renogram outweigh any risks. A doctor will have checked the request to make sure this is the appropriate test for you.
If you have any concerns or would like further information, please contact the nuclear medicine radiographers in the scanning department. If you don’t understand why you need to have this test please speak to the doctor who referred you.
Radiation can be harmful for an unborn baby. If you know that you are pregnant, or there is any chance that you may be pregnant, then please contact the department. Do this as soon as possible as the scan can be postponed if it is not urgent.
Also contact the department if you are breast-feeding, as they may give you special instructions.
If you are urinary incontinent, require a hoist, or if you have other tests or appointments within 24hours after your renogram please contact the scanning department before your scan.
If you self-catheterise we will require you to bring your own supply of catheters.
Unfortunately we are unable to offer childcare facilities. If you have young children or babies please do not bring them to your appointment.
Unless your doctor has told you to have restricted fluids, please make sure that you drink plenty of water before the renogram. You can eat normally.
If you are taking diuretic medicines please contact the department where you will be having your renogram for particular advice. You can take any other medicine as normal.
The radiographer will ask you if you are happy for the renogram to go ahead. This is a form of verbal consent and may only involve the radiographer checking you are booked for the correct procedure. If you do not wish to have the renogram or are undecided, please ask the radiographer so that they can answer any questions you may have. Remember, it is your decision. You can change your mind at any time and your wishes will be respected. However, not having the bone scan may delay your diagnosis as the doctors may not have all the needed information.
Just before your scan you will be asked to go to the toilet to empty your bladder.
You will not have to get undressed, but you will be asked to remove any metal objects like braces, jewellery and belts before the test starts.
The pictures are taken by a special machine called a gamma camera. You will be asked to lie on a bed or sit on a special chair with the camera behind your back. You will be asked your height (cm)and weight (Kg). There may also be another camera detector in front of you.
A small amount of radioactive tracer will be injected into a vein in your arm. You may have had a blood test in the past and it is similar to that.
The ‘pinprick’ of the needle may hurt a bit but that is all.
Another injection will be given of a diuretic, which is a substance which makes your kidneys work harder and produce more urine. This will be given after the injection of radioactive tracer through the same vein access.
You then just have to lie or sit still for about 30 minutes whilst the gamma camera takes a series of pictures of the tracer passing through your kidneys. If you need to go to the toilet during the scan please ask the radiographer undertaking the scan.
Some further pictures may be taken after the initial scan once you have been to the toilet; these are known as delayed images.
The effect of the diuretic will wear off after a few hours, but you may feel the need to go to the toilet more frequently or urgently. Please bear this in mind when you are travelling home or planning your activities for the next few hours. You should continue to drink plenty of fluids in order to replace what has been lost in your urine.
It is very unlikely that you will feel any other side-effects after the scan, but if you think that you have please let the nuclear medicine department know.
After the renogram you may continue all your normal activities unless you have been advised otherwise.
After your scan there will be some radioactivity left in your body but this will not present a significant risk to other people around you. However, for the rest of the day, we suggest that you try to keep any time that you spend with pregnant women, babies and small children as short as possible; but there is no need to stop giving children essential love and care. The radioactivity in your body will soon disappear.
You will be given advice with regards to safe disposal of any items which may have become contaminated with the tracer from your urine such as catheters and catheter bags.
It is perfectly safe for you to travel abroad after your scan, but many airports and sea ports are now equipped with very sensitive radiation detectors. So it is possible that the very small amount of radioactivity left in your body could set off a detector as you pass through security. Therefore, if you intend to travel abroad within a week following your scan, it could be helpful to take with you something to explain that you have recently had a nuclear medicine scan. This could be your appointment letter or some other official confirmation from the department where you had your scan.
Your renogram pictures will be processed to produce a graph showing how quickly the tracer passes through your kidneys and into your bladder.
The result will be looked at by a specialist doctor, who will issue a report. The report will be sent to the doctor who requested your test rather than to your GP. This is because the doctor who requested your test will have all the results from other tests and will be able to tell you how the result of your renogram affects your care.
It is very unlikely that you will feel any side-effects after the scan, but if you think that you have please let the nuclear medicine department know.
You may continue all your normal activities unless you have been advised otherwise. If you feel your condition has changed, or you need further medical advice before receiving your results, please make an appointment with the doctor that referred you, or in an emergency, go to your local accident and emergency (A&E) department.
For advice, support or to raise a concern, contact our Patient Advice and Liaison Service (PALS). To make a complaint, contact the complaints department.
Telephone: 020 8909 5439 (PALS)
Email: rnoh.
Telephone: 020 8909 5717 / 5439 / 5741 (Complaints)
Email: rnoh.
Offers medical help and advice from fully trained advisers supported by experienced nurses and paramedics. Available over the phone 24 hours a day.
Telephone: 111
If you have any questions or concerns about coming for your renogram, please contact the x-ray reception on 020 8909 5801 (Monday to Friday, 9am to 5pm).
Page last updated: 17 February 2025