Diatrizoate excretion

CM can be classified according to osmolality, which reflects the total particle concentration of the solution (the number of molecules dissolved in a specific volume) (1,2), CM with osmolality greater than that of blood may be more difficult for the kidney to excrete. Over the past 40 years, the osmolalities of available CM have been gradually decreased to physiologic levels. In the 1950s, only high-osmolar CM (e.g., diatrizoate)... 

Urinary excretion of water-soluble contrast agents is by glomerular filtration without any tubular reabsorption (689). The CLR for the contrast medium was compared with the clearance of Cr-EDTA, injected alone or co-injected with the contrast medium, given that Cr-EDTA is known for its excretion by glomerular filtration only (759, 765). The elimination half-life ty usually expresses urinary excretion in a comparable term for water-soluble contrast agents. In addition to the values given above, iotrolan has a ty2 of 106 min and diatrizoate, 108 min. According to Olssen et al. (759),... 

Absorption and excretion of metrizamide and diatrizoate after suboccipital injection in the cat followed first-order kinetics. Golman and Dahl (766) determined the rate constants for absorption and excretion and observed that 99% of the absorbed dose disappeared from cerebrospinal fluid during the 3 h after suboccipital injection. The difference in the to-... 

Urinary excretion is the principal means of elimination for diatrizoate, iothalamate, met-rizoate, metrizamide, and other urographic agents (688, 767, 782, 783). Diatrizoate, iothalamate, and metrizamide were excreted in the urine of the rabbit to the extent of more than 80% 24 h after injection (768,783-785). The total recovery including the amount excreted in feces 96 h after injection was about 91.5% of the dose for metrizamide, 93.8% for diatrizoate, and 86.0%for iothalamate (782). 

Contrast agents cause osmotic diuresis. Studies show that sodium diatrizoate is excreted in higher concentration in the urine than is meglumine diatrizoate because of resorption of sodium ions in the renal tubules. Benness (790, 878) reported a difference in roentgenographic quality in pyelogramsin favor of sodium contrast agents. 

Urine iodine concentration, after the injection of nonionic metrizamide. is about twice as high as after sodium diatrizoate injection. Gol-man et al. (795) reported that during the periods of ureteric stasis, metrizamide was excreted faster than diatrizoate. Nonionic iopamidol reduces the incidence of adverse reactions in excretory urography and produces equal quality urograms with less iodine than diatrizoate (881). 

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