Hypersensitivity reactions
Ultravist can be associated with anaphylactoid / hypersensitivity or other idiosyncratic reactions characterized by cardiovascular, respiratory and skin manifestations.
Allergic-type reactions are possible from mild to severe reactions, including shock (see section "Undesirable effects"). Most of these reactions occur within 30 minutes after administration. However, there may be delayed reactions (after hours to days).
The risk of hypersensitivity reactions is greater in case of:
- previous reaction to contrast media
- history of bronchial asthma or other allergic disorders
A particularly careful risk / benefit assessment is required in patients with known hypersensitivity to Ultravist or to any Ultravist excipient, or to a previous hypersensitivity reaction to any other iodinated contrast medium due to the increased risk of hypersensitivity reactions (including severe reactions) .
However, such reactions are irregular and unpredictable in nature. Patients who have such reactions while taking beta-blockers may be refractory to the effects of treatment with beta-agonists (see also the section "Interactions with other medicines and other forms of interaction"). In the case of a severe hypersensitivity reaction, patients with cardiovascular disease are more susceptible to serious or even fatal consequences.
Due to the possibility of severe hypersensitivity reactions after administration, postprocedural observation of the patient is recommended.
It is necessary to be prepared to institute emergency measures for all patients. Premedication with a corticosteroid regimen may be considered in patients with an increased risk of acute allergic-type reactions, in patients with a previous moderate or severe acute reaction, asthma or allergy who require medical treatment.
Thyroid dysfunction
A particularly careful risk / benefit assessment is required in patients with known or suspected hyperthyroidism or goiter, since iodinated contrast media can induce hyperthyroidism and thyrotoxic crisis in these patients. The thyroid function test before the administration of Ultravist and / or of the preventive thymostatic medication can be considered in patients with known or suspected hyperthyroidism.
It is recommended to monitor the thyroid function in neonates, especially premature infants, who have been exposed to Ultravist, through the mother during pregnancy or in the neonatal period, since exposure to an excess of iodine can cause hypothyroidism, possibly requiring treatment.