Inform your doctor if you are on any medications, have any allergies or underlying medical conditions before going for a CT scan. You may not be a good candidate for a CT scan if you are pregnant, since there is a likelihood for the X-rays to harm your baby. Depending on your condition and the area examined, you may be asked not to eat or drink anything for a few hours before your procedure. Avoid wearing any metal objects such as jewellery or cloths with metal zippers or buttons while going for a CT scan. Even though CT scans have not been known to cause long-term damage, be aware that CT scans expose you to a minimum amount of ionizing radiation that can increase your risk of cancer.
In order to better visualize the images, you may receive an injection of a contrast material before your CT scan. The contrast may be given orally or rectally depending on the area examined. Some people can be allergic to the contrast material and may develop rashes or itchiness. Be sure to inform your doctor if you have ever had any allergies to similar substances before your CT scan.