UROGRAFIN

What it is

Urografin is a solution containing sodium amidotrizoate and amidotrizoate meglumine, supplied as an oral liquid with 10 g sodium amidotrizoate and 66 g amidotrizoate meglumine per 100 mL. It is a clear, faintly yellowish, aqueous, ionic, hypertonic solution. Urografin is an iodine-containing contrast medium, with iodine being radio-opaque.

Approved indications

Urografin is a contrast medium for examination of the gastrointestinal tract, administered orally or rectally, and is primarily indicated in cases in which the use of barium sulfate is unsatisfactory, undesirable or contraindicated. These include: — Suspected partial or complete stenosis. — Acute haemorrhage. — Threatening perforation, such as in peptic ulcer or diverticulum. — Other acute conditions which are likely to require surgery. — After resection of the stomach or the intestine, due to danger of perforation or leak. — Megacolon. — Visualisation of a foreign body or tumour before endoscopy. — Visualisation of gastrointestinal fistula. — Early diagnosis of a radiologically undetectable perforation or anastomotic defect in the oesophagus or gastrointestinal tract. — Treatment of meconium ileus. — Computerised tomography in the abdominal region.

Dosing overview

For adults and children aged 10 years and over, visualisation of the stomach requires 60 mL, and follow-through examination of the gastrointestinal tract requires a maximum of 100 mL. For elderly and cachectic patients, dilution with an equal volume of water is recommended. Babies and young children require 15–30 mL diluted with three times its volume of water, while children up to 10 years of age require 15–30 mL which can be diluted with twice its volume of water. For computerised tomography, examination is performed after administration of 1.0–1.5 L of approximately 3% Urografin solution, prepared as 30 mL Urografin per litre of water. For rectal administration in adults, up to 500 mL of diluted Urografin (diluted with 3–4 times its volume of water) is used.

Key safety warnings

Particularly careful risk–benefit assessment is required in patients with known hypersensitivity to Urografin due to increased risk of anaphylaxis or hypersensitivity reactions, which can be characterised by cardiovascular effects such as hypotension, respiratory effects such as wheeze, gastrointestinal effects such as nausea and vomiting, or cutaneous effects such as urticaria and pruritus, and can range to severe reactions including shock. The reported incidence of adverse reactions to contrast media is higher in patients with a history of allergy such as seafood allergy, hay fever, hives, sensitivity to iodine, radiographic media sensitivity, or bronchial asthma. Particularly careful risk–benefit assessment is required in patients with known or suspected hyperthyroidism or goitre, as iodinated contrast media may interfere with thyroid function, aggravate or induce hyperthyroidism and thyreotoxic crisis. In neonates, especially preterm infants, who have been exposed to Urografin, it is recommended to monitor thyroid function, as exposure to excess iodine may cause hypothyroidism, possibly requiring treatment. In case of prolonged retention of Urografin in the gastrointestinal tract, such as with obstruction or stasis, tissue damage, bleeding, bowel necrosis and intestinal perforation may occur. Adequate hydration must be assured before and after contrast medium administration, particularly in patients with multiple myeloma, diabetes mellitus, nephropathy, polyuria, oliguria, hyperuricaemia, newborns, infants, small children and elderly patients, and disturbances of water and electrolyte balance must be corrected before examination.

Contraindications

Manifest hyperthyroidism is a contraindication. Urografin must not be administered undiluted in patients with low plasma volume, such as newborns, infants, children, and dehydrated patients, since hypovolemic complications can be particularly serious in these patients. Urografin must not be administered undiluted in patients with suspected possibility of aspiration or broncho-oesophageal fistula, since hyperosmolarity may cause acute pulmonary oedema, chemical pneumonia, respiratory collapse and death.

Regulatory history

Urografin was first approved on 19 August 1991. Two variants were subsequently listed on the Australian Register of Therapeutic Goods in 1992: Urografin 30% 250 mL injection bottle and Urografin 30% 10 mL injection ampoule, both first listed on 22 September 1992.