Iohexol, sold under the trade name Omnipaque among others, is a contrast agent used for X-ray imaging.

[4] This includes when visualizing arteries, veins, ventricles of the brain, the urinary system, and joints, as well as during computed tomography (CT scan).

[5] Side effects include vomiting, skin flushing, headache, itchiness, kidney problems, and low blood pressure.

[14] It is also sold as a density gradient medium under the names Accudenz, Histodenz, and Nycodenz.

[13] Iohexol can given as intrathecal, intravascular, oral, rectal, intraarticular, or into the body cavity.