Iodine Allergic Reaction-How long

Hi.  at 7 this morning i had a cat scan done and they used iodine for the contrast agent. if i were allergic to iodine how quickly would it take for my reaction to show immediately or over some time??  i feel fine right now but i just want to know if i have to look out for anything later tonight.

[Bhupinder Kaur, MD]

Hello,

Allergies can occur with any contrast agent, whether injected into a vein or ingested orally. The signs of contrast reaction to iodine are skin hives(reddened splotchy areas on the skin (face, trunk, arms) that develop soon after injection. They can be very itchy and uncomfortable and take several days to go away), throat tightening or laryngeal edema, facial puffiness, difficulty in breathing and wheezing and sudden drop in the BP causing dizziness, increased heart beat and cold clammy extremities.

Some patients experience headaches, muscle pains and flu-like symptoms up to 48 hours after contrast media. This is a self limited reaction.

If you see any of the above signs, then pls consult the ER immediately to avoid any life threatening anaphylaxis.

Hope it helped. Take care and regards.