Propyliodone (INN, trade name Dionosil) is a molecule used as a contrast medium. It was developed by a team at Imperial Chemical Industries in the late 1930s. Propyliodone used as radiopque medium for brochographic use. When directly instilled into the bronchi resulting in well-defined bronchograms for atleast 30 min. Because of its toxicity, Propyliodone should only be used if absolutely essential. It is of Synthetic origin and belongs to Iodinated Radio-opaque Compounds. It belongs to Radiopaque Agents pharmacological group on the basis of mechanism of action and also classified in Diagnostic Aids pharmacological group. Oral absorption of Propyliodone is found to be 101% and metabolism is reported Lungs and Gut wall. Propyliodone is primarily indicated in conditions like Paget's disease of bone, Radiological contrast agent. Propyliodone produces potentially life-threatening effects which include Fever, Anaphylaxis, Repiratory obstruction, Cerebral embolization, which are responsible for the discontinuation of Propyliodone therapy. The signs and symptoms that are produced after the acute overdosage of Propyliodone include Airway obstruction. The symptomatic adverse reactions produced by Propyliodone are more or less tolerable and if they become severe, they can be treated symptomatically, these include Headache, Fever, Malaise, Nausea and vomiting, Aching joints.

Iodipamide is used as a contrast agent for cholecystography and intravenous cholangiography. Following intravenous administration of Cholografin Meglumine, iodipamide is carried to the liver where it is rapidly secreted. The contrast medium appears in the bile within 10 to 15 minutes after injection, thus permitting visualization of the hepatic and common bile ducts, even in cholecystectomized patients. Iodipamide (Cholografin Meglumine) is indicated for intravenous cholangiography and cholecystography as follows: (a) visualization of the gallbladder and biliary ducts in the differential diagnosis of acute abdominal conditions, (b) visualization of the biliary ducts, especially in patients with symptoms after cholecystectomy, and (c) visualization of the gallbladder in patients unable to take oral contrast media or to absorb contrast media from the gastrointestinal tract. The biliary ducts are readily visualized within about 25 minutes after administration, except in patients with impaired liver function. The gallbladder begins to fill within an hour after injection; maximum filling is reached after two to two and one-half hours. Organic iodine compounds block x-rays as they pass through the body, thereby allowing body structures containing iodine to be delineated in contrast to those structures that do not contain iodine. The degree of opacity produced by these iodinated organic compounds is directly proportional to the total amount (concentration and volume) of the iodinated contrast agent in the path of the x-rays. Iodipamide's primary excretion through the hepato-biliary system and concentration in bile allows visualization of the gallbladder and biliary ducts.

BETAZOLE is a histamine H2 receptor agonist used clinically to test gastric secretory function.

Acetrizoic acid (trade names Gastrografina, Urografina in Portugal) is a palatable lemon-flavored water-soluble iodinated radiopaque X-ray contrast medium for oral or rectal administration only. Acetrizoic acid is indicated for radiographic examination of segments of the gastrointestinal tract (esophagus, stomach, proximal small intestine, and colon). The preparation is particularly indicated when a more viscous agent such as barium sulfate, which is not water-soluble, is not feasible or is potentially dangerous. Administration of hypertonic Gastrografin solutions may lead to hypovolemia and hypotension due to fluid loss from the intestine.

Aminohippurate (p-aminohippuric acid, PAH, PAHA) is the glycine amide of p-aminobenzoic acid. Aminohippuric acid sodium salt is an agent to measure effective renal plasma flow (ERPF).

Thorium dioxide, a main component of Thorotrast that was used as a contrast agent for cerebral angiography. Thorotrast is an alpha emitter and primary site of deposition is the reticuloendothelial system including the liver, spleen, bone marrow, and lymph nodes. However was discovered, that this compound can cause hepatic angiosarcoma with a long latent period. That is why this contrast agent was withdrawn.

Dimecrotic acid is a choleretic agent with spasmolytic properties. It is obtained by reaction of resorcinol with acetoacetate to give 4-methyl-7-hydroxycoumarin. It is indicated for the treatment of hepato-digestive insufficiency and its manifestations. It shouldn’t be used in case of blockage of bile ducts, severe liver failure and severe renal impairment. Diarrhea may be associated with high doses of dimecrotic acid.

Uridine 5'-triphosphate (UTP, INS316) is a naturally occurring agonist for P2Y(2) receptors on the apical surface of ciliated respiratory epithelium. INS316, being developed by Inspire Pharmaceuticals, is a short-acting, aerosolized uridine 5-triphosphate (UTP) solution used as a diagnostic aid for lung cancer. INS316 appears to improve sputum expectoration mediated through the P2Y2 receptor, a nucleotide receptor expressed in human airway epithelial cells and some other tissues. UTP binding to the P2Y2 receptor triggers signal transduction that leads to chloride ion secretion, thereby resulting in mucociliary clearance of airway. UTP stimulates salt and water transport and cilia beat frequency in human airway epithelium in vitro. Single, inhaled doses of UTP stimulate mucociliary clearance in conscious, intubated sheep and in patients with mild chronic bronchitis (smokers and former smokers), suggesting that UTP may be useful for obtaining deep-lung sputum specimens suitable for diagnostic purposes. A single dose of INS316 safely improves the ability of patients with mild chronic bronchitis to expectorate a deep-lung sputum specimen suitable for cytologic evaluation.

Perflenapent (EchoGen, Sonus Pharmaceuticals, Bothel, WA, USA) is a transpulmonary echocardiographic contrast agent for use in patients with suspected or established cardiovascular disease to provide opacification of cardiac chambers, enhance left ventricular border delineation with resulting improvement in wall motion visualisation. EchoGen comprises liquid droplets of dodecafluoropentane stabilised by polyfluoroalkyl(polyoxyethylene) ethanol and dispersed in an aqueous formulation containing sucrose. Dodecafluoropentane is the chemical name used to reflect the perflenapent/perflisopent mixture. Following activation and administration of EchoGen, dodecafluoropentane microbubbles are formed. EchoGen should only be used in patients where the study without contrast enhancement is inconclusive. The European Commission has approved SONUS Pharmaceuticals' EchoGen (perflenapent emulsion) in all 15 countries of the European Union. EchoGen is a fluorocarbon-based ultrasound contrast agent which has been approved as a transpulmonary echocardiographic contrast agent for use in patients with suspected or established cardiovascular disease who have had previous inconclusive non-contrast studies. Additional approved labeling in the EU states that the use of EchoGen in spectral and color Doppler studies was shown to enhance the visualization of blood flow across mitral, aortic and tricuspid valves in a subset of patients. In 2000 SONUS Pharmaceuticals withdrew the NDA for EchoGen in the USA.

Technetium (99mTc) exametazime is a radiopharmaceutical agent, which is known as trade name Ceretec. The Ceretec kit is supplied as five packs of three vials for use in the preparation of a technetium Tc99m exametazime intravenous injection as a diagnostic radiopharmaceutical. When technetium Tc99m pertechnetate is added to exametazime in the presence of stannous reductant, a lipophilic technetium Tc99m complex is formed. This lipophilic complex is the active moiety. It converts at approximately 12%/hour to less lipophilic species. When the secondary complex is separated from the lipophilic species, it is unable to cross the blood-brain-barrier. The useful life of the reconstituted agent is limited to 30 minutes. This complex is used as an adjunct in the detection of altered regional cerebral perfusion in stroke. And in addition, is indicated for leukocyte labeled scintigraphy as an adjunct in the localization of intra-abdominal infection and inflammatory bowel disease. Also exist clinical trials, where this complex is used for diagnostic purposes in Crohn's Disease and in vascular prosthesis infection.