Iodixanol is an iodine-containing non-ionic radiocontrast agent. It is sold under the trade name Visipaque; it is also sold as a density gradient medium under the name OptiPrep. Visipaque is commonly used as a contrast agent during coronary angiography. It is the only iso-osmolar contrast agent, with an osmolality of 290 mOsm/kg H2O, the same as blood. It is sold in 2 main concentrations 270 mgI/ml and 320 mgI/ml - hence the name Visipaque 270 or 320. It is sold in single dose units and a large 500ml plastic bottle for multi-dose dispensing. Iodixanol is an iodine-containing non-ionic radiocontrast agent. It is sold under the trade name Visipaque; it is also sold as a density gradient medium under the name OptiPrep. Visipaque is commonly used as a contrast agent during coronary angiography. It is the only iso-osmolar contrast agent, with an osmolality of 290 mOsm/kg H2O, the same as blood. It is sold in 2 main concentrations 270 mgI/ml and 320 mgI/ml - hence the name Visipaque 270 or 320. It is sold in single dose units and a large 500ml plastic bottle for multi-dose dispensing.