Are there any risks to the test? 
You should not take this test if you are pregnant or think you may be pregnant. Radiation can be harmful to an unborn baby.
For others, there is little risk to having this test. The dose of radiation is very low and is not considered harmful for most people. But talk to your provider about all the x-rays you've had in the past. The risks from radiation exposure may be linked to the number of x-ray treatments you've had over time.
There is a small risk of an allergic reaction to the contrast dye. Tell your provider if you have any allergies, especially to shellfish or iodine, or if you've ever had a reaction to contrast material.
Other risks include headache and nausea and vomiting. The headache may last for up to 24 hours. Serious reactions are rare but may include seizures, infection, and a blockage in the spinal canal.
