What is an alternative to iodine used in ct with contrast? say, someone is allergic to shellfish....what is an alternative contrast to use?

See below: Mri is one alternative or Benadryl (diphenhydramine) and Prednisone prioir to the procedure if absolutely necessary.

Reaction to contrast: Contrast media reactions are often described as allergy but in truth are not allergy. The high concentration of the contrast can shock cells called basophils into releasing their granules filled with histamine. This causes the same reaction as the histamine release due to allergy. Shellfish allergy has nothing to do with iodine or contrast. Low osmolality contrast & premedication helps.

Get: Premedicated if your worried and have the test. Shell fish allergy doesn't really increase your risk of allergy to contrast in my opinion. I have a shell fish allergy so i understand your concern. If my patients are worried, i premedicate them.

Not related: Shellfish allergy and contrast reactions are not related. The major shellfish allergen is tropomyosin. The issue with contrast reactions is related to the concentration of the dye used.