HRs to CM can be distinguished in immune-mediated and non-immune-mediated reactions, even if clinical manifestations could be similar. Manifestations range from mild skin eruptions to severe anaphylaxis, making it important for radiologists to know how to identify and manage them. A panel of experts from the SIRM and the SIAAIC provided a consensus document on the management of patients who must undergo radiological investigations with CM.

The most important recommendations are that a thorough medical history must be taken by the prescribing physician and/or the radiologist to identify at-risk patients. In patients with hypersensitivity reactions to CM, the radiologist must consider an alternative, non-contrast imaging study with a comparable diagnostic value, or prescribe a different investigation with another class of CM. If such options are not feasible, the radiologist must address at-risk patients to a reference center for an allergy evaluation. If a timely referral to an allergist is not viable, it is recommended to use a CM other than the responsible one, taking into account cross-reactivity patterns; in the case of patients with histories of severe reactions, the presence of an anesthesiologist is also recommended and premedication is suggested.