You are scheduled for a nuclear scan which involves the injection of a special material that contains minute amounts of radioactivity. The amount of radioactivity to which you will be exposed is less than that of a chest X-ray, so you needn't worry about excess exposure. The radiologist in charge will take pictures (not X-rays) of the area under study. In your case we will be studying the kidneys. This test will help determine overall kidney function, especially comparing the right kidney to the left kidney. It will also show signs of blockage.
Other than minute amounts of radiation there are minimal risks with this procedure. With the dye injection there is a very small chance of an allergic reaction. A physician will be in attendance in case a reaction occurs.
No restrictions of diet, fluids or medications exist for this examination.