Patterns of plasma iron fractions after intramuscular Ferastral

The distribution of plasma iron fractions after intramuscular Ferastral is described for times up to eight days after injection. Transferrin-bound iron reaches a peak value in 4-8 hours and falls towards normal values while circulating iron-complex concentration remains high. The peak concentration of iron-complex occurs 8-24 hours after injection, and is virtually cleared from the circulation in 6-8 days. An approximate T 1/2 of 30 hours for plasma Ferastral is deduced from the rate of fall from peak values. UIBC values fell as transferrin-bound iron increased, but did not reach zero in any subject studied.