Corticosteriods
Looks like they would use the corticosteroids as pretreatment for someone that might be expected to have a reaction. What I thought. Found this:
"Pretreatment
Iodinated contrast material injection should be avoided, whenever possible, in any patient who has had a previous moderate or severe anaphylactoid reaction to iodinated contrast material. If contrast material injection must be performed (because imaging with contrast material is necessary and no alternative imaging study will provide the desired information), corticosteroid premedication must be provided, if at all feasible. It is also suggested that steroid premedication be given to patients who have had previous mild allergic-like contrast reactions, such as hives, although there is no uniformity of opinion on this issue. Steroid premedication should also be strongly considered in patients with multiple or severe allergies to other agents, and in patients with symptomatic or poorly controlled asthma. Two pretreatment regimens have been widely researched. The first utilizes two oral 32 mg doses of methylprednisolone administered 12 hours and 2 hours before contrast material injection (11), while the second requires administration of 50 mg of prednisone 13 hours, 7 hours, and 1 hour prior to contrast media injection.(12) The latter regimen also usually includes a 1-hour pre-procedural oral dose of 50 mg of diphenhydramine."