meglumine amidotrizoate + sodium amidotrizoate: clinical use

Prescribing considerations

• Confirm the required route and product: Gastrografin contains additives that prohibit intravascular use, while Urografin 150 for Infusion is intended for vascular and renal imaging.
• Assess previous iodinated-contrast reactions, atopy or asthma, cardiovascular status, thyroid disease, renal and hepatic function, diabetes, neurological disease, myeloma and hydration.
• Correct significant fluid or electrolyte disturbance and avoid restricting fluids in vulnerable patients unless clinically required.
• Ensure facilities and trained staff for immediate management of hypersensitivity reactions; observe intravascular recipients closely after administration.
• Urografin is not suitable for myelography.

Contraindications and cautions

• Hypersensitivity or proven or suspected hypersensitivity to iodine-containing contrast media.
• Manifest or uncontrolled hyperthyroidism or thyrotoxicosis.
• Decompensated cardiac insufficiency for Urografin.
• Hysterosalpingography during pregnancy or acute pelvic inflammation.
• Undiluted Gastrografin in hypovolaemic or dehydrated patients, including infants and children.
• Undiluted Gastrografin where aspiration or a broncho-oesophageal fistula is suspected.

Monitoring

• Assess renal function where clinically indicated, particularly before intravascular use in patients with kidney disease, diabetes or other risk factors.
• Maintain and monitor hydration and electrolyte balance, especially with enteral Gastrografin or bowel obstruction.
• Monitor during and after administration for immediate hypersensitivity or cardiovascular reactions; advise that delayed reactions can occur.
• Consider thyroid assessment in known or suspected hyperthyroidism and monitor thyroid function in exposed neonates, especially those born preterm.
• Monitor injection sites for extravasation and bowel progress where Gastrografin retention or obstruction is a concern.

Clinical pharmacology

Amidotrizoate is an ionic, water-soluble, high-osmolar iodinated contrast agent without a therapeutic pharmacodynamic effect in routine imaging. Oral absorption is low; following intravascular administration it distributes extracellularly and is predominantly eliminated unchanged by glomerular filtration.

Formulation and product differences

• Gastrografin is a gastroenteral solution for oral or rectal use and contains flavouring-related additives; it must not be administered intravascularly.
• Urografin 150 for Infusion is an aqueous injectable solution for vascular and renal imaging.
• Both products contain sodium, but their concentrations, excipients, authorised routes and clinical uses differ.