ct/cat scans are a highly useful addition to a hospital medical arsenal. sadly, this technology is not without risk. the iodine based contrast that is often used in these studies can put a strain on the kidneys of the patient. the contrast is administered through an iv into the blood stream and is necessary for the arteries to be visible in the scan. for the average patient the strain is minimal and easily overcome without any medical assistance. for high risk patients, however, there is a risk of kidney damage from the contrast. at risk patients include, but are not limited to, the elderly, diabetic, and heart disease patients. recent studies have been conducted to try protect the kidneys from the contrast being used. most notably is the drug n-acetylcysteine or nac. use of this medication before the introduction of the contrast has been shown to reduce the effects of the contrast by up to ninety percent. like all medications, nac comes with its own side effects. i am not advocating that anyone self medicate, nor am i doctor. but if you do feel that your kidneys are compromised in some way you may want to ask your doctor about taking nac before undergoing a ct scan, angiogram, or other procedure where iv iodine contrast is used.

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nac on wikipedia