Patients who are allergic to the contrast dye in an angiogram question

Editorial Team / Admin · Mar 11, 2014

Good article here (and it's short ): http://www.uphs.upenn.edu/ppmc_emergency/PPMC%20Bookmarks/Premedication%20for%20IV%20Contrast/HUP%20BODY%20CT%20SECTION.pdf

Has to do with blocking the receptors. :)

BriGuyRN · Apr 1, 2014

Allergic reactions to contrast dye typically involve inflammation (such as anaphylaxis), so prednisone could be given to prevent or decrease the amount of inflammation.

Unfortunately there aren't many alternatives to an angiogram when it comes to diagnosing CAD

MunoRN, RN · Apr 4, 2014

An important part of understanding contrast allergies is that it's not actually possible to be allergic to iodine. It's often referred to as an "allergy" (with intentional quotation marks). The iodine itself, other components of the solution, and even the osmolarity of the solution itself can cause a histamine release, but not a true allergic reaction.

Regardless of the etiology, the end result is still a localized/systemic inflammatory response (but much more limited than a true allergic reaction), which still makes anti-inflammatory and antihistamine treatments effective.

delphine22 · Apr 11, 2014

Our protocol is Benadryl, Solucortef and Pepcid, all IV.

Agree with MunoRN, though I did have a pt once that reported a true anaphylactic reaction to contrast dye, he coded in the cath lab due to it.

Editorial Team / Admin · Apr 11, 2014

We see a LOT fewer reactions to contrast than we used to, since the development of non-ionic, iso-osmolar contrast agents (Omnipaque, Visipaque, for example).

They still contain iodine.

Which makes one wonder just what is the reactive ingredient??

Bottom line: be prepared at any time for a reaction to ANYTHING (antibiotics, prescription or OTC meds, bee stings, etc), even if one has not previously had a reaction.

Sensitivity can develop AT ANY TIME, and WITHOUT WARNING.

(I always carry Benadryl)

(off-topic but pertinent:

I had a severe allergic response to a bee sting while we were out camping with friends.

Had NEVER had problems with stings before.

It developed and progressed quickly.

Luckly dh had Benadryl with him and I took two.

Being the nurse that I am, I did not call 911, but monitored myself [yeah, I know; but you know how we are!!!] for an hour.

Airway wasn't compromised but there was significant swelling of the neck [i looked like Jabba the Hut, when I finally got to a mirror] and face.

I could tell airway was encroached upon but trusted the Benadryl to decrease the severity of the swelling.

Yes I now carry an Epi-pen.

and Benadryl.

And counsel all to carry Benadryl with them.

That is all, carry on! :) )

MunoRN, RN · Apr 12, 2014

We see a LOT fewer reactions to contrast than we used to, since the development of non-ionic, iso-osmolar contrast agents (Omnipaque, Visipaque, for example).
They still contain iodine.
Which makes one wonder just what is the reactive ingredient??
....

The osmolarity of older dyes is often blamed, there are also numerous preservatives, stabilizers, dilutents, etc, all of which are possible culprits. Out of all of them, the iodine is by far the least likely culprit, yet for some reason it's become synonymous with a contrast allergy.

Up until about 75 years ago it was considered common scientific knowledge that shellfish allergies were due to the increased iodine content of shellfish, then we learned that different types of meat actually present very different antigens and that the iodine had nothing to do with it, yet you'll still find many in the medical community who consider a shellfish allergy to be synonymous with an iodine allergy, some myths just take many generations to go away.

delphine22 · Apr 12, 2014

Up until about 75 years ago it was considered common scientific knowledge that shellfish allergies were due to the increased iodine content of shellfish, then we learned that different types of meat actually present very different antigens and that the iodine had nothing to do with it, yet you'll still find many in the medical community who consider a shellfish allergy to be synonymous with an iodine allergy, some myths just take many generations to go away.

I did not know this! Thanks MunoRN, I will do more research into this to inform others on my floor (we are the pre-/post-intervention floor).

MunoRN, RN · Apr 12, 2014

I did not know this! Thanks MunoRN, I will do more research into this to inform others on my floor (we are the pre-/post-intervention floor).

The relationship of radiocontrast, iodine, and s... [J Emerg Med. 2010] - PubMed - NCBI

Is Shellfish Allergy Related to Iodine?

Shellfish allergy Prevention - Diseases and Conditions - Mayo Clinic

T-Bird78 · Apr 15, 2014

Bottom line: be prepared at any time for a reaction to ANYTHING (antibiotics, prescription or OTC meds, bee stings, etc), even if one has not previously had a reaction.
Sensitivity can develop AT ANY TIME, and WITHOUT WARNING.
(I always carry Benadryl)
(off-topic but pertinent:
I had a severe allergic response to a bee sting while we were out camping with friends.
Had NEVER had problems with stings before.
It developed and progressed quickly.
Luckly dh had Benadryl with him and I took two.
Being the nurse that I am, I did not call 911, but monitored myself [yeah, I know; but you know how we are!!!] for an hour.
Airway wasn't compromised but there was significant swelling of the neck [i looked like Jabba the Hut, when I finally got to a mirror] and face.
I could tell airway was encroached upon but trusted the Benadryl to decrease the severity of the swelling.
Yes I now carry an Epi-pen.
and Benadryl.
And counsel all to carry Benadryl with them.
That is all, carry on! :) )

LIQUID BENADRYL!!!!!