Iohexol
Indications
Iohexol is used for:
Radiographic contrast medium for diagnostic procedures
Adult Dose
Intravascular
Angiocardiography: ventriculography, pulmonary arteriography, venography & studies of collaterol arteries
Ventriculography: 40 mL, range of 30-60 mL; may be repeated as needed, not to exceed 250 mL
Selective Coronary Arteriography: 5 mL. range 3-14 mL per injection
Aortic Root and Arch Study: 50 mL, range 20-75 mL, when used alone
Pulmonary Angiography: 1 mL/kg
Combined Angiographic Procedures: Multiple Procedures not to exceed 5 mL/kg or 250 mL
Aortography and Selective Arteriography
- Aorta: 50-80 mL
- Major branches incl celiac, mesenteric arteries: 30-60 mL
- Renal arteries: 5-15 mL; not to exceed 250 mL/Iohexol 350 when repeat injection indicated
Cerebral Arteriography: Common Carotid Artery: 6-12 mL
Internal Carotid Artery: 8-10 mL
External Carotid Artery: 6-9 mL
Vertebral Artery: 6-10 mL
CT Scanning of the Body
Head Imaging via injection: 70-150 mL (Iohexol 300); 80 mL (Iohexol 350)
Body Imaging via injection: 50-200 mL (Iohexol 300); 60-100 mL (Iohexol 350)
Digital Subtraction
Iohexol 350
Usual amount used for IV digital technique is 30-50 mL
Administer as bolus at 7.5-30 mL/sec using pressure injector
Excretory Urography
Iohexol 300/350: 200-350 mgI/kg body weight
Hysterosalpingography
Iohexol 300: 15-20 mL, but varies with anatomy and/or disease state
Child Dose
Intravascular
Iohexol 300/350
Angiocardiography: ventriculography, pulmonary arteriography, venography & studies of collaterol arteries
Ventriculography: Iohexol 350: 1.25 mL/kg, range 1-1.5 mL/kg; not to exceed 5 mL/kg or 250 mL, when multiple injections given
Iohexol 300: 1.75 mL/kg, range 1.5-2 mL/kg; not to exceed 6 mL/kg or 291 mL, when multiple injections given
Pulmonary Angiography: 1 mL/kg
Combined Angiographic Procedures - Multiple Procedures
-Iohexol 350: Not to exceed 5 mL/kg or 250 mL
-Iohexol 300: Not to exceed 6 mL/kg or 291 mL
Aortography and selective arteriography: 1 mL/kg single inj dose; not to exceed 5 mL/kg or 250 mL
CT Scanning of the Body
Head imaging: 1-2 mL/kg; not to exceed 35 gI Iohexol 300
Body imaging via injection: 50-200 mL (Iohexol 300); 60-100 mL (Iohexol 350)
Excretory Urography
Iohexol 300: 0.5-3 mL/kg of body weight
Infants/children: According to age and body weight
Usual dose: 1-1.5 mL/kg; not to exceed 3 mL/kg
Renal Dose
Administration
Contra Indications
Procedure-specific. Intrathecal: Myelography in significant local or systemic infection where bacteremia is likely; concurrent use with corticosteroids; repeat myelography in the event of technical failure (risk of overdosage). Hysterosalpingography: During menstrual period or when menstrual flow in imminent; presence of infection; pregnancy, 6 mth after termination of pregnancy or 30 days after conization or curettage.
Precautions
Asthma or a history of allergies (risk of anaphylactoid reactions is increased); compromised blood-brain barrier (severe neurotoxicity after intrathecal use); epilepsy and brain tumour (higher risk of convulsions); severe hepatic or renal impairment, diabetics with renal impairment, dehydration and others who may be at increased risk of renal failure; multiple myeloma (dehydration from use may cause precipitation of protein in the renal tubules, leading to anuria and fatal renal failure); severe hypertension; advanced cardiac disease; phaeochromocytoma; sickle-cell disease; hyperthyroidism; debilitated, severely ill, very old, or very young patients; occlusive vascular disease. Special care to ensure that 140 and 350 mg iodine/ml solutions are not given intrathecally. Adequate resuscitative facilities should be available when radiographic procedures are undertaken, and patients should be kept under observation for a suitable period after the procedure.
Lactation: Not known; not recommended
Pregnancy-Lactation
Interactions
Adverse Effects
Side effects of Iohexol :
Flushing or a sensation of heat; pain, extravasation, thrombophlebitis at the inj site; nausea, vomiting, headache, and dizziness; urticaria, pruritus, pallor, sweating, metallic taste, weakness, coughing, rhinitis, sneezing, lachrymation, visual disturbances; hypotension, tachycardia, bradycardia, transient ECG abnormalities, haemodynamic disturbances; dyspnoea, bronchospasm, angioedema, severe urticaria; convulsions, paraesthesia, paralysis; acute renal failure; thromboembolism, disseminated intravascular coagulation, thrombocytopenia; hyperthyroidism, thyroid storm thyrotoxicosis.
Potentially Fatal: Profound hypotension, pulmonary oedema, respiratory arrest, ventricular fibrillation, circulatory failure, cardiac arrest, coma.
Mechanism of Action
Allows for radiographic visualization through the opacification of vessels and anatomical structures in the path of flow of the contrast media.