Water-soluble intravascular iodinated

Water-soluble intravascular iodinated contrast agents [SED-15, 1848 SEDA-31, 731 SEDA-33, 963]... 

All the products available for intravascular injection are water soluble, whereas the chemicals given by oral route are lipid soluble. Their basic structure is made up of a benzene nucleus with three iodine atoms in positions 2, 4, and 6 (these provide the necessary radiologic contrast). Position 1 is an acidic site which seems to play a role in solubilizing the product. Different chains may occupy positions 3 and 5 and their nature seems to influence the general tolerance of the specific chemicals. There are numerous variations on the basic structure, most of these being salts of... 

There are four types of iodinated water-soluble contrast media, classified according to their physicochemical properties (Table 1). They are mainly used intravascularly but can also be injected into body cavities, particularly the low-osmolar contrast agents. Some are also used for oral or rectal administration, and the high-osmolar water-soluble contrast agent diatrizoate is suitable only for these purposes. Low-osmolar and iso-osmolar iodinated contrast media have almost completely replaced high-osmolar agents for intravascular use and administration into body cavities. 

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