CT with and without contrast

I had my first appointment yesterday and I’ve been given a referral for a “CT with and without contrast.” Does this mean they will do a CT with contrast and then another without? Or does it mean I can choose? I have allergic reactions sometimes so I’d rather skip the contrast if I can, but does anyone know what difference it makes?

The contrast is useful if you suspect that you have vascular ES, there’s info in the Newbies Guide about VES symptoms if you’re not sure. It’s up to you though if you don’t want the contrast, just have the CT without it…I don’t know for sure, but I imagine they’d do the without contrast first and then the contrast one after.


@Skatkat, @Jules is correct. The CT is done w/o contrast first then an IV is inserted in your arm & contrast is given for the second CT. The dye used for CT scans is iodine based so if you’re not allergic to iodine, it won’t be likely to bother you. I’ve had a couple of CTs w/ contrast & get a burning sensation in my arm for a few seconds after the dye is injected & then a bladder response for a few seconds where I’ve felt the urgency to urinate. The radiology techs usually alert you to these possible effects which are very momentary.