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Getting ready for urinary tract imaging: why, getting ready, the tests, and after
For anyone sent for an x-ray, ultrasound, MRI, CT or nuclear scan of the kidneys, ureters, bladder or urethra. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK, part of the NIH) says imaging creates pictures of the organs inside the body and helps health care professionals see the cause of a problem. This page passes on, by name, what NIDDK says: why imaging may be needed; what you may be asked and how to get ready; how each kind of test works; and afterward, the discomfort, the signs of infection or a reaction, what dye can mean for your kidneys, and the results. It builds the words to say and the questions to ask, and prints a card for the fridge.
Right now
- Trouble breathing, a swollen face or throat, chest pain, or fainting? Call 911 (ours).
- After the test: pain, chills, or fever after a catheter; hives, itching, nausea, vomiting, headache, or dizziness after dye; or changes in breathing or heart rate after a sedative? NIDDK says call your health care professional immediately.
- Told to fast for the test and you take diabetes medicine or any daily medicine? Ask what to do with it. Do not stop or change a prescribed medicine on your own (ours).
- Scared of what the pictures may show, or thinking of ending your life? Call or text 988, any hour (ours).
More help
- The kidneys and bladder, on this site: Kidney stones · Blood in the urine · Bladder infections · Kidney disease · Getting ready for a cystoscopy or ureteroscopy · Kidneys, bladder and urine: find the right page.
- Getting ready: My medicines list · Get ready for your appointment · Rides to care.
- Care and costs: When you need a doctor and can’t pay · Medical bills.
- In a crisis: Help right now (988, 911). All our free tools.
Kidneys, bladder or urine, and not sure this is the right page? The pages on this site for bladder infections, kidney stones, blood in the urine, bladder pain, bladder leaks, the prostate, kidney disease and bedwetting, on one list.
This page and its wording were written with AI (Claude) for Scarlet Beast (our AI policy). No doctor or nurse has reviewed it. The facts were read on October 17, 2026 on NIDDK’s Urinary Tract Imaging page (NIH) and its Spanish version, both last reviewed in April 2020 and saying the same things; the cards also point to NIDDK’s The Urinary Tract & How It Works, Kidney Stones and Hematuria (Blood in the Urine) pages. The numbers (water 2 hours before some ultrasounds; an enema about 4 hours before a transrectal ultrasound; fasting for 12 hours; an antibiotic for 1 or 2 days after a catheter; kidney damage from dye healing within a week or so in most people; results of some tests in several days) are NIDDK’s. Ours: 911 for trouble breathing, a swollen face or throat, chest pain, or fainting; asking what to do with diabetes medicine or any daily medicine while you fast, and never stopping or changing a prescribed medicine on your own; asking which test and whether it uses dye; telling them about your kidneys and diabetes first; that it is fine to ask them to tell you each step; asking who gives the results and when; the card; 988 when it is too much; health centers when money is tight; and the order of the steps. What we left out: medicine names, brands and doses, the kinds of dye, the encyclopedia pages NIDDK links for each technique, and the clinical trials section. This page saves nothing and loads no trackers.