VISIPAQUE

What it is

Iodixanol is a non-ionic, dimeric, hexaiodinated, water-soluble X-ray contrast medium. VISIPAQUE is supplied as iodixanol injection in strengths of 270 mg I/ml and 320 mg I/ml. VISIPAQUE is supplied ready to use as clear, colourless to pale yellow aqueous solutions. Pure aqueous solutions of iodixanol in all clinical relevant concentrations have a lower osmolality than whole blood and the corresponding strengths of the non-ionic monomeric contrast media. VISIPAQUE is made isotonic with normal body fluids by addition of electrolytes.

Approved indications

VISIPAQUE is indicated, in adult patients, for angiocardiography, peripheral arteriography, visceral arteriography, cerebral arteriography, contrast-enhanced computed tomography of the head and body, excretory urography and venography. In arteriography, VISIPAQUE may be used for both conventional radiography and digital subtraction angiography (DSA). In children, VISIPAQUE is indicated for cardioangiography, urography, CT-enhancement and studies of the upper gastrointestinal tract.

Dosing overview

The combination of volume and concentration of VISIPAQUE to be used should be carefully individualised, accounting for factors such as age, body weight, size of the vessel, rate of blood flow within the vessel, cardiac output, indication for examination, and timing of the X-ray or CT scan. Other factors to be considered are anticipated pathology, degree and extent of opacification required, structure or area to be examined, disease processes affecting the patient, and equipment and technique used. Usually approximately the same iodine concentration and volume is used as with other iodinated X-ray contrast media in current use, but adequate diagnostic information has also been obtained in some studies with iodixanol injection with somewhat lower iodine concentration.

Key safety warnings

Iodinated contrast media may provoke anaphylactoid reactions or other manifestations of hypersensitivity. A course of action should therefore be planned in advance, with necessary drugs and equipment available for immediate treatment, should a serious reaction occur. Encephalopathy has been reported with the use of iodixanol. Contrast encephalopathy may manifest with symptoms and signs of neurological dysfunction such as headache, visual disturbance, cortical blindness, confusion, seizures, loss of coordination, hemiparesis, aphasia, unconsciousness, coma and cerebral oedema within minutes to hours after administration of iodixanol and generally resolves within days. The product should be used with caution in patients with conditions that disrupt the integrity of the blood brain barrier (BBB), potentially leading to increased permeability of contrast media across the BBB and increasing the risk of encephalopathy. If contrast encephalopathy is suspected, administration of iodixanol should be discontinued and appropriate medical management should be initiated. Patients should be well hydrated prior to, and following, administration of any contrast medium, including VISIPAQUE, in order to prevent from acute renal failure. This applies especially to patients with multiple myeloma, diabetes mellitus, renal dysfunction and elderly patients. Preparatory dehydration is dangerous and may contribute to acute renal failure in patients with pre-existing renal insufficiency, diabetes or advanced vascular disease. To prevent lactic acidosis, serum creatinine level should be measured in diabetic patients treated with metformin prior to intravascular administration of iodinated contrast medium. Normal serum creatinine/renal function: administration of metformin should be stopped at the time of administration of the contrast medium and not resumed for 48 hours or until renal function/serum creatinine is normal.

Contraindications

Hypersensitivity to the active substance or iodine or hypersensitivity to any of the excipients. History of serious hypersensitivity reaction to VISIPAQUE. Manifest thyrotoxicosis.

Regulatory history

VISIPAQUE iodixanol was first listed on the ARTG on 27 June 1995, with multiple presentations registered including 550 mg/ml and 652 mg/ml injection vials, bottles and bags. Additional presentations including 10 ml, 20 ml, 40 ml and 50 ml ampoules were first listed on 30 November 2000. The TGA approved an application to extend the indications of VISIPAQUE to include paediatric use on 14 May 2010.