Which statement regarding DELAYED (late) adverse reactions to iodinated contrast media is correct?

• A They occur within 60 seconds of injection and are always IgE mediated
• B They require adrenaline therapy in the majority of cases
• C They occur exclusively in patients with normal renal function
• D They occur from 1 hour up to about 48 hours after injection and are usually mild and self-limiting ✓

Explanation

Delayed reactions appear between 1 hour and 48 hours after contrast administration, with a peak around 6 to 12 hours. They typically manifest as rash, pruritus or mild urticaria and resolve spontaneously, needing only antihistamines or topical steroids. They are more frequent with iso-osmolar dimeric agents such as iodixanol. Immediate reactions occur within the first hour, and adrenaline is reserved for immediate severe anaphylaxis, not delayed mild eruptions.

Reference: ACR Manual on Contrast Media, 2023 ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.