Hi,
Ive had CT's done without Contrast too.

I found out I am allergic to the contrast in June this year when having a CT for possible bowel obstruction.

The allergic reaction was really scary - temperature went up to 38, had been 36 earlier. Face swelled , neck swelled and I was covered in hives. I got quite short of breath. I panic now if I ever need a CT with contrast again.

Years ago I had a CT with contrast and was absolutely fine - but I now seem to develop allergies to medications very regularly now.

Rach