Disposition in rats of the carbohydrate polymer in Ferastral--an iron-poly (sorbitol-gluconic acid) complex.

The disposition and pharmacokinetics in rats of 14C-sorbitol-Ferastral has been studied as an initial step towards elucidating the metabolic fate of the polymeric organic moiety. The period of time studied was 24 h. Following i.v. administration of a dose corresponding to 10 mg/kg of iron approximately 60% of the isotope was found in the urine after this period of time. A further 3% was demonstrated in the faeces whilst the expired air accounted for about 10% in the form of 14CO2. Thus, a relatively large proportion of the radiolabel was promptly excreted via the kidneys whilst the expired air and probably bile constituted secondary excretion routes. The physico-chemical nature of the urinary product was similar to the parent carbohydrate compound. The residual 14C radioactivity was distributed mainly between the liver, which contained approximately 45% of the retained label, carcass with 36% and large intestine with 7%. The plasma disappearance pattern was biphasic. Similar experiments with the 14C-sorbitol polymer starting material were performed for purposes of comparison.