OMNIPAQUE

What it is

OMNIPAQUE is iohexol supplied as a solution for injection in strengths of 180 mgI/mL, 240 mgI/mL, 300 mgI/mL, and 350 mgI/mL. OMNIPAQUE is supplied ready to use as clear, colourless to pale yellow, sterile aqueous solutions. This medicinal product is for diagnostic use only. OMNIPAQUE contains no preservative.

Approved indications —

Angiography in adults — Excretory urography in adults — Contrast enhancement in computerised tomography in adults — Angiography in children — Urography in children — Arthrography in adults — Endoscopic retrograde pancreatography (ERP) in adults — Endoscopic retrograde cholangiopancreatography (ERCP) in adults — Herniography in adults — Hysterosalpingography in adults — Studies of the gastrointestinal tract in adults, children and premature babies — Lumbar, thoracic, cervical and total columnar myelography in adults and children — Computerised tomography of the CNS in adults and children

Dosing overview

The lowest dose of OMNIPAQUE necessary to obtain adequate visualisation should be used. The combination of volume and concentration of OMNIPAQUE to be used should be carefully individualised accounting for factors such as age, body weight, size of the vessel and the rate of blood flow within the vessel. Adequate hydration should be assured before and after administration as with other contrast media. Dosing varies significantly by indication and route of administration. For urography in adults, the usual dose is 200 mg I/kg with a maximum dose of 400 mg I/kg (40–80 mL, with 80 mL which may be exceeded in selected cases) using 300 mg I/mL or 350 mg I/mL by intravenous injection. For children under 7 kg, the dose is up to 3 mL/kg, and for children over 7 kg, up to 2 mL/kg (maximum 40 mL) using 300 mg I/mL. For intrathecal use, a total dose of 3 g iodine should not be exceeded.

Key safety warnings

Adequate hydration should be assured before and after contrast media administration, especially in patients with multiple myeloma, diabetes mellitus, renal dysfunction, infants, small children and elderly patients. Use of iodinated contrast media may cause increase in serum creatinine and acute kidney injury, and special care should be exercised in patients with pre-existing renal impairment and diabetes mellitus as they are at risk. A positive history of allergy, asthma, or untoward reactions to iodinated contrast media indicates a need for special caution, and premedication with corticosteroids or histamine H1 and H2 antagonists might be considered. The possibility of hypersensitivity including serious life-threatening fatal anaphylactoid reactions should always be considered, with a course of action planned in advance and necessary drugs and equipment available for immediate treatment. Special attention should be paid to paediatric patients below 3 years of age because an incident underactive thyroid during early life may be harmful for motor, hearing, and cognitive development. The incidence of hypothyroidism in patients younger than 3 years of age exposed to iodinated contrast media has been reported and is more commonly observed in neonates and premature infants. Thyroid function should be evaluated in all paediatric patients younger than 3 years of age following exposure to iodinated contrast media, and if hypothyroidism is detected, the need for treatment should be considered and thyroid function should be monitored until normalised. Encephalopathy has been reported with the use of iohexol. 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, with symptoms usually occurring within minutes to hours after administration and generally resolving within days. After contrast medium administration the patient should be observed for at least 30 minutes, since the majority of serious side effects occur within this time, although delayed reactions may occur one hour or more after application.

Contraindications

OMNIPAQUE is contraindicated in patients with hypersensitivity to the active substance or to any of the excipients, or with a history of serious reaction to OMNIPAQUE. Iodine-containing radiographic contrast media should not be administered to patients with thyrotoxicosis, anuria or decompensated cardiac insufficiency. These agents are also contraindicated in carotid angiography during the progressive period of stroke; coronary arteriography in the first 4 weeks after myocardial infarction; and in the presence of infection or open injury in or near the region to be examined. Do not administer with intrathecal corticosteroids. For hysterosalpingography, the procedure is contraindicated in pregnant women or for those in whom pregnancy is suspected, and use is not advised for 6 months after termination of pregnancy or 30 days after conization or curettage.

Regulatory history

OMNIPAQUE 180, 240, 300 and 350 mg I/mL were first registered on the Australian Register of Therapeutic Goods on 10 September 1991. Additional presentations in various vial and bottle sizes were registered from 1992 onwards, with ampoule formulations registered from 2000. The most recent registrations occurred on 10 November 2021 for OMNIPAQUE 300 and 350 mg I/mL in 500 mL bottles.