There is a chance of an allergic reaction to the dye, even if the patient has received prior injections of contrast without incident. Physicians should seek alternative imaging of the urinary system for patients with documented allergies to iodinated contrast, including retrograde pyelography (performed by urologists), MRI, or ultrasound.

There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most experts feel that the risk is low compared with the benefits.

Pregnant women and children are more sensitive to the risks of the X-ray.