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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.
Another test coming up, or not sure this is the right page? The guides on this site for a colonoscopy, an endoscopy, a GI series, ERCP, a biopsy, a cystoscopy, urodynamic tests, urinary tract imaging, prostate tests, an A1C and thyroid tests, on one list.
Other guides on this site that go with this page
Free to read. We chose these ourselves; no professional did. Each guide was written with AI and has not been reviewed by a professional. They are general information, not advice.
- Hydronephrosis in newborns (a swollen kidney in a baby): the causes, the tests, and the treatment: hydronephrosis in a newborn (a swollen kidney in a baby, found on a pregnancy ultrasound or after birth): what it is and how common, when it is a sign of a problem, the causes, the tests before and after birth, and the treatment.
- Perineal injury in males (an injury between the legs): the signs, the causes, and the treatment: perineal injury in males (an injury between the legs): what it is and who is more likely, the signs, what it can lead to, the tests and treatment, and protecting yourself.
- Kidney infection (pyelonephritis): the signs, sepsis, and the treatment: a kidney infection (pyelonephritis): the signs at each age, sepsis and when it is 911, who is more likely to get one, the tests, the antibiotics, and preventing the next one.
- Ectopic kidney: what it is, the problems it can cause, the tests, and the treatment: an ectopic kidney (a kidney out of its usual place: a pelvic kidney, crossed renal ectopia), often found by chance or on an ultrasound in pregnancy: what it is, what causes it, how common it is, the problems it can cause (reflux, blockage, infections, kidney stones, injury), the symptoms, the tests, the treatment, and living with one working kidney.
- Vesicoureteral reflux (VUR) in a child: urine flowing back toward the kidneys, the grades, UTIs, the tests, antibiotics and surgery, and good habits: vesicoureteral reflux (VUR) in a child: urine flowing back from the bladder toward the kidneys; the grades; primary and secondary VUR; how common it is and who is more likely; UTIs and kidney scarring; the ultrasound and VCUG; antibiotics, surgery and bulking injections; and good habits.
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.