Is the dye use for Pet Scans have any side effects?

It depends how you define "side effects", silly goose; the primary side effect of using a contrast dye is that the Radiologist will be better able to accurately diagnose what may or may not be causing your husband's symptoms; if he has any fear about "side effects" then he has a rather unrealistic understanding of risk & real life and should probably seek to fix that, it will make him a happier, safer & more productive person...

To illustrate how "silly" his question is, think about this; do seat belts have any negative side-effects? Yes, they do...several people die every year from injuries caused by seat-belts....but since literally hundreds of thousands of lives are saved by them each year, would it make any logical sense not to wear one because of that?

Of course not...

Not usually. Patients who have an allergy to seafood can sometimes react to iodine when that is used as the contrast dye. You can google "iodine contrast side effects".

does your sugar level goes up after the dye or the sugar drink?