Diatrizoate is the most commonly used water-soluble, iodinated, radiopaque x-ray contrast medium. Radiopaque agents are drugs used to help diagnose certain medical problems. They contain iodine, which blocks x-rays. Depending on how the radiopaque agent is given, it localizes or builds up in certain areas of the body. The resulting high level of iodine allows the x-rays to make a “picture” of the area. The areas of the body in which the radiopaque agent localizes will appear white on the x-ray film. This creates the needed distinction, or contrast, between one organ and other tissues. The contrast will help the doctor see any special conditions that may exist in that organ or part of the body.
The dosage is based on the specific imaging test, age, and weight.
Mechanism of Action
Diatrizoate is an iodine-containing X-ray contrast agent. Iodated contrast agents were among the first contrast agents developed. Iodine is known to be particular electron-dense and to effectively scatter or stop X-rays. A good contrast agent requires a high density of electron-dense atoms. Therefore, the more iodine, the more “dense” the x-ray effect. Iodine based contrast media are water soluble and harmless to the body. These contrast agents are sold as clear colorless water solutions, the concentration is usually expressed as mg I/ml. Modern iodinated contrast agents can be used almost anywhere in the body. Most often they are used intravenously, but for various purposes they can also be used intraarterially, intrathecally (the spine) and intraabdominally – just about any body cavity or potential space.
However, it is not metabolized but excreted unchanged in the urine, each diatrizoate molecule remaining “obligated” to its sodium moiety. The liver and small intestine provide the major alternate route of excretion for diatrizoate. Injectable radiopaque diagnostic agents are excreted unchanged in human milk. Saliva is a minor secretory pathway for injectable radiopaque diagnostic agents.
Used, alone or in combination, for a wide variety of diagnostic imaging methods, including angiography, urography, cholangiography, computed tomography, hysterosalpingography, and retrograde pyelography. It can be used for imaging the gastrointestinal tract in patients allergic to barium.