Iopentol is a non-ionic X-ray contrast medium. It contains a tri-iodinated benzene ring, which, due to a high atomic density of iodine, causes hight attenuation of X-rays. Iopentol It has been used in various radiologic procedures to aid the radiographic visualization of selected tissues and organs. Iopentol is not commercially available in the United States, but was marketed in Europe under tradename Imagopaque for arteriography, urography, phlebography and computed tomography enhancement, arthrography, endoscopic retrograde cholangiopancreatography, hysterosalpingography, and gastrointestinal studies.

Iobenzamic acid is a contrast medium, which was used for cholecystography under the name Osbil. It is assumed that the drug is no longer marketed.

Iotroxic acid (INN), also known as meglumine iotroxate (BAN) (Biliscopin) for infusion is indicated for radiological examination of the hepatic and biliary ducts and gallbladder when examination by oral technique is unsuccessful or inappropriate. Following intravenous administration Biliscopin is rapidly excreted, mainly by the liver into the bile. Visualisation of the hepatic and common bile ducts and the gallbladder can, therefore, be achieved. Visualisation of the biliary ducts is usually possible 30-60 minutes after completion of administration. In vitro meglumine iotroxate binds to plasma proteins to the extent of 60-90% depending on concentration. In animals it crosses the placental barrier. This agent is the single intravenous cholangiographic agent, which is currently available in Australia.

Iodine-labeled ioglycamic acid (Bilivistan or Biligram) has been used as a contrast medium for intravenous cholangiocystography.

Ioxitalamic acid is a contrast media, which was used as a meglumine salt under the name Telebrix for intravenous urography; computed tomography; digital angiography; angiocardiography (ventriculography, coronary angiography). The drug is no longer available on the market.

Ioglicinate, contrast agent, is used in computed tomography.

Iobitridol is a contrast medium used for intravenous urography, cerebral computed tomography, computed tomography of the whole body, digital subtraction angiography, arteriography, angiocardiography, venography, CT scan of the thorax. The drug is marketed under the name Xenetix.

Iocarmic acid is a molecule used in seventies as a contrast media for myelography. Iocarmate meglumine (Dimer-X), a water-soluble salt of iocarmic acid was reported to be safe and best tolerated by central nervous system compared to metrizamide in a double-blind test in patients with symptoms of lumbar and sacral root involvement. In the experimental and clinical studies of Dimer-X used for ventriculography the apparent superiority of Dimer-X over Conray 60 and Angiografin as far as side effects were concerned was demonstrated, but there were no particular differences in the intensities of the ventriculograms obtained. Morphological studies of the ventricles and histological examinations of the ventricular walls 1 month after injections of Dimer-X into the ventricles of dogs showed no abnormalities. In the clinical studies, ventriculography Dimer-X, performed on patients with diseases of the central nervous system, produced ventriculograms of good diagnostic value with no side effects, such as convulsions, apart from mild headache or vomiting in 4 instances. Ventriculography with Dimer-X was carried in 15 infants with myelomeningocele and progressive hydrocephalus. However, as was shown in a number of studies iocarmate produced moderate to severe arachnoiditis from myelography in primates. Early meningitis side effects following lumbar radiculography with iocarmate meglumine were demonstrated.