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Overview

 Parenterally administered iron does not give a faster response compared to oral administration, therefore, the rate of recovery from anemia should be the same. Reticulocyte count will increase in 3-4 days and peak in 7-10 days. Hemoglobin may increase at a rate of 1.5-2.2 g/dl/week for the first 2 weeks, followed by 0.7 to 1.6 g/dl/week until normal hemoglobin levels are achieved. Parenteral iron treatment should be administered only when iron deficiency is not correctable with oral treatment.  Note: Iron dextran is cleared by the reticuloendothelial system.  Smaller doses (50-500mg) are cleared within 3 days, however, larger doses(>500mg) are cleared at a constant rate of 10-20mg/hr and are associated with increased plasma concentration of iron dextran for as long as 3 weeks. 

  Iron replacement for blood loss: Dose (mg)= Blood loss (ml) x Hematocrit %. Total mg of iron/50 = dose in ml.   Reactions to IV administration include: fever, chills, backache, myalgia, dizziness, syncope,rash and anaphylaxis-immediate or delayed.   

Total dose infusion: the overall consensus regarding IV administration of iron dextran is that total dose infusion is the preferred method. If severe reactions develop, multiple bolus injections over several days may be required.   Average total body content of iron in adult male: 4 grams (70% in Hgb, 25% in storage). 

 The first changes seen with treatment is an increase in  reticulocytes (4-6 days initially, peak: 9-12 days) Hemoglobin will rise slowly--it should rise by 2 g/dl after 3 weeks. The plasma iron will gradually increase, and the initially elevated TIBC will return to normal in about one month. Blood levels return to normal in about 4-6 months (ferritin levels will return to normal). Laboratory: Transferrin: delivers iron to bone marrow and storage sites. Circulating transferrin is normally only about 30% saturated with iron. The remaining 70% in unbound and represents the TIBC. Iron is stored as either ferritin or hemosiderin within macrocytes (reticuloendothelial system). Normal RBC survival time: 120 days.  

In iron deficiency anemia (microcytic-hypochromic=decreased Hemoglobin), iron stores are depleted prior to anemia; therefore, the earliest change observed is usually decreased ferritin. Hemoglobin: Normal (female): 12-16 g/dL ; Male 14-18 g/dL.  Hematocrit: Normal (female): 35-40% ; (Male): 42-52%. A low Hematocrit  indicates a decrease in number or size of RBC or increase in plasma volume. RBC count: 4.5 to 6 million/ml (4 to 5.5 female). MCV(mean corpuscular volume): indicates microcytic, normocytic or macrocytic morphology.  MCH(mean corpuscular hemoglobin): Average weight of Hgb in RBC. Decreased in microcytosis and hypochromia(low hgb). MCH alone cannot distinguish between the two. MCHC(mean corpuscular hemoglobin conc.): (Nml: 31-36%): weight of Hemoglobin/volume of cells. Independent of cell size and, therefore, is more useful than MCH in distinguishing between microcytosis and hypochromia. A low MCHC always indicates hypochromia, as a microcyte with a normal Hemoglobin concentration will have a low MCH but a normal MCHC. Red cell distribution width (RDW): Normal: 11.4 - 14.5% Indicates how much the RBC's vary in size. Elevated in anemia's resulting from nutritional deficiencies (iron,folic acid, B12). Serum iron concentration: concentration of iron bound to transferrin. Unfortunately, the serum level of many patients with iron deficiency anemia remains within the lower limits of normal. There is a 20-30% diurnal variation in serum iron levels--it is best to draw levels in the morning. Total iron binding capacity (TIBC): indirect measurement of serum transferrin. Unlike the serum iron level, the TIBC is remarkably constant. The finding of a low serum iron and a high TIBC indicates iron deficiency anemia. Serum ferritin: the concentration of ferritin (storage iron) in the serum is proportional to total iron stores. Low ferritin levels are virtually diagnostic of iron deficiency anemia as they are decreased only in iron deficiency anemia. Liver disease causes an elevation in serum ferritin; thus ferritin should not be used for diagnostic purposes in patients with even mild hepatic pathology.

References

2.  Bhowmik D, Modi G, Ray D, Gupta S, Agarwal SK, Tiwari SC, Dash SC. Total dose iron infusion: safety and efficacy in predialysis patients. Ren Fail. 2000 Jan;22(1):39-43.

3.  Burns DL, Mascioli EA, Bistrian BR. Parenteral iron dextran therapy: a review.  Nutrition. 1995 Mar-Apr;11(2):163-8.

4.  Case G. Maintaining iron balance with total-dose infusion of intravenous iron dextran. ANNA J. 1998 Feb;25(1):65-8.

5.  Hanson DB, Hendeles L. Guide to total dose intravenous iron dextran therapy.  Am J Hosp Pharm. 1974 Jun;31(6):592-5.

6.  Jacobs P, Dommisse J.  The plasma ferritin level as a reliable index of body iron stores following intravenous iron dextran. J Med. 1982;13(4):309-21.

7.  Koda-Kimble MA, Applied Therapeutics for Clinical Pharmacists, 2nd ed, edited by Koda-Kimble et al, Applied Therapeutics, Inc., San Francisco 1978. 

8.  Kumpf VJ.  Parenteral iron supplementation. Nutr Clin Pract. 1996 Aug;11(4):139-46.

9.  Kumpf VJ, Holland EG. Parenteral iron dextran therapy. DICP. 1990 Feb;24(2):162-6. 

10.  Low CL, Bailie GR, Eisele G.  Sensitivity and specificity of transferrin saturation and serum ferritin as markers of iron status after intravenous iron dextran in hemodialysis patients. Ren Fail. 1997 Nov;19(6):781-8.

11.  Sloand JA, Shelly MA, Erenstone AL, Schiff MJ, Talley TE, Dhakal MP.  Safety and efficacy of total dose iron dextran administration in patients on home renal replacement therapies. Perit Dial Int. 1998 Sep-Oct;18(5):522-7.