Iopentol (trade name Imagopaque) is a pharmaceutical drug that was used as a

radiocontrast agent Radiocontrast agents are substances used to enhance the visibility of internal structures in X-ray-based imaging techniques such as computed tomography ( contrast CT), projectional radiography, and fluoroscopy. Radiocontrast agents are typically i ...

for

X-ray imaging Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. Applications of radiography include medical radiography ("diagnostic" and "therapeut ...

in Europe.

Medical uses

Uses included

arteriography Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins, and the heart chambers. Modern angiography is perform ...

(imaging of

arteries An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body (tissues, lungs, brain etc.). Most arteries carry oxygenated blood; the two exceptions are the pu ...

venography Venography (also called phlebography or ascending phlebography) is a procedure in which an x-ray of the veins, a venogram, is taken after a special dye is injected into the bone marrow or veins. The dye has to be injected constantly via a catheter ...

(imaging of the

veins Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated b ...

) and CT scan enhancement,

urography Pyelogram (or pyelography or urography) is a form of imaging of the renal pelvis and ureter. Types include: * Intravenous pyelogram – In which a contrast solution is introduced through a vein into the circulatory system. * Retrograde pyelogram ...

(imaging of the

urinary system The urinary system, also known as the urinary tract or renal system, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressure, c ...

arthrography An arthrogram is a series of images of a joint after injection of a contrast medium, usually done by fluoroscopy or MRI. The injection is normally done under a local anesthetic such as Novocain or lidocaine. The radiologist or radiographer perfor ...

(imaging of the joints),

endoscopic retrograde cholangiopancreatography Endoscopic retrograde cholangiopancreatography (ERCP) is a technique that combines the use of endoscopy and fluoroscopy to diagnose and treat certain problems of the biliary or pancreatic ductal systems. It is primarily performed by highly skille ...

(ERCP; imaging of bile and

pancreatic duct The pancreatic duct, or duct of Wirsung (also, the major pancreatic duct due to the existence of an accessory pancreatic duct), is a duct joining the pancreas to the common bile duct. This supplies it with pancreatic juice from the exocrine pancr ...

hysterosalpingography Hysterosalpingography (HSG), also known as uterosalpingography, is a radiologic procedure to investigate the shape of the uterine cavity and the shape and patency of the Fallopian tubes. It is a special x-ray using dye to look at the womb (ute ...

(imaging of the

uterus The uterus (from Latin ''uterus'', plural ''uteri'') or womb () is the organ in the reproductive system of most female mammals, including humans that accommodates the embryonic and fetal development of one or more embryos until birth. The ...

and

fallopian tubes The fallopian tubes, also known as uterine tubes, oviducts or salpinges (singular salpinx), are paired tubes in the human female that stretch from the uterus to the ovaries. The fallopian tubes are part of the female reproductive system. In ot ...

), and

gastrointestinal The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans and ...

studies. It can be injected into blood vessels or body cavities or given

by mouth Oral administration is a route of administration where a substance is taken through the mouth. Per os abbreviated to P.O. is sometimes used as a direction for medication to be taken orally. Many medications are taken orally because they are i ...

Contraindications

Hysterosalpingography is contraindicated during acute inflammation in the pelvic region.

Adverse effects

Adverse effects include

nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...

, vomiting, headache, as well as low or high blood pressure or heart rate. Allergy-like reactions such as rashes are usually mild; glottal edema,

shock Shock may refer to: Common uses Collective noun *Shock, a historic commercial term for a group of 60, see English numerals#Special names * Stook, or shock of grain, stacked sheaves Healthcare * Shock (circulatory), circulatory medical emergen ...

and

cardiac arrest Cardiac arrest is when the heart suddenly and unexpectedly stops beating. It is a medical emergency that, without immediate medical intervention, will result in sudden cardiac death within minutes. Cardiopulmonary resuscitation (CPR) and poss ...

are rare.

Interactions

Iodine-131 Iodine-131 (131I, I-131) is an important radioisotope of iodine discovered by Glenn Seaborg and John Livingood in 1938 at the University of California, Berkeley. It has a radioactive decay half-life of about eight days. It is associated with nu ...

, a radioactive

isotope Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numb ...

used for thyroid imaging (

scintigraphy Scintigraphy (from Latin ''scintilla'', "spark"), also known as a gamma scan, is a diagnostic test in nuclear medicine, where radioisotopes attached to drugs that travel to a specific organ or tissue (radiopharmaceuticals) are taken internally and ...

) and therapy of

thyroid cancer Thyroid cancer is cancer that develops from the tissues of the thyroid gland. It is a disease in which cells grow abnormally and have the potential to spread to other parts of the body. Symptoms can include swelling or a lump in the neck. C ...

s, can be less effective when used within two to six weeks after application of iopentol because of residual iodine in the body.

Pharmacology

Chemistry and mechanism of action

Iopentol is an iodine-containing, water-soluble radiocontrast agent. The iodine atoms readily absorb

X-rays An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nbs ...

, resulting in a higher contrast of X-ray images. It has a low

osmolality Molality is a measure of the number of moles of solute in a solution corresponding to 1 kg or 1000 g of solvent. This contrasts with the definition of molarity which is based on a specified volume of solution. A commonly used unit for molali ...

, meaning that the solution has a relatively low concentration of molecules; this is usually associated with fewer adverse effects than high-osmolality contrast agents. A phase III

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, diet ...

concluded that iopentol produces images of a similarly high quality as

iohexol Iohexol, sold under the trade name Omnipaque among others, is a contrast agent used for X-ray imaging. This includes when visualizing arteries, veins, ventricles of the brain, the urinary system, and joints, as well as during computed tomograp ...

, and that it is equally well tolerated by patients.

Pharmacokinetics

After intravenous injection, iopentol is distributed in the

extracellular space Extracellular space refers to the part of a multicellular organism outside the cells, usually taken to be outside the plasma membranes, and occupied by fluid. This is distinguished from intracellular space, which is inside the cells. The compos ...

. Its binding to

plasma protein Blood-proteins, also termed plasma proteins, are proteins present in blood plasma. They serve many different functions, including transport of lipids, hormones, vitamins and minerals in activity and functioning of the immune system. Other blood pr ...

s is very low. The substance is not metabolized, but excreted in unchanged form via the kidneys, exclusively by

glomerular filtration Renal functions include maintaining an acid–base balance; regulating fluid balance; regulating sodium, potassium, and other electrolytes; clearing toxins; absorption of glucose, amino acids, and other small molecules; regulation of blood pre ...

. Only 2% are excreted in the faeces. The

biological half-life Biological half-life (also known as elimination half-life, pharmacologic half-life) is the time taken for concentration of a biological substance (such as a medication) to decrease from its maximum concentration ( Cmax) to half of Cmax in the bl ...

is two hours.

References

{{Contrast media Radiocontrast agents Benzamides Acetanilides Iodobenzene derivatives