Iron : Dosing

by MedlinePlus

(Page 2 of 4)

General:

Carbonyl iron (Feosol®) has a slower release of iron and is more expensive than ferrous sulfate. Slower release preparations may be safer in children and cause less gastrointestinal side effects. 45mg and 60mg carbonyl iron tablets are available.

Once weekly iron supplementation has been shown to be equally as effective as daily supplement in improving iron status and reducing the prevalence of iron deficiency in the preschool children. Once a week dosing was shown to reduce transient iron overload and gastrointestinal side effects caused by daily iron supplementation in another study. A conflicting study indicates that there is no significant absorptive advantage in giving iron less often than once daily.

Oral iron therapy may be ineffective in individuals with diarrhea, post-gastrectomy, or other malabsorption syndromes. Decreased stomach acidity (achlorhydria) may impair iron absorption.

Adults (18 years and older):

Recommended Dietary Allowance (RDA): Males (19- 50 years): 8mg/day; Females (19- 50 years) 18mg/day; Adults (51 years and older) 8mg/day; pregnant women (all ages) 27mg/day; breastfeeding women (19 years and older) 9 mg/day.

Tolerable Upper Intake Level (UL): Adults (19 years and older) 45mg/day.

Vegetarians: Because iron from plant sources is less efficiently absorbed than that from animal sources, the U.S. Food and Nutrition Board (FNB) has estimated that the bioavailability of iron from a vegetarian diet is only 10%, while it is 18% from a mixed diet. Therefore, the recommended dietary allowance (RDA) for iron from a completely vegetarian diet should be adjusted as follows: 14mg/day for adult men and postmenopausal women, 33mg/day for premenopausal women, and 26mg/day for adolescent girls.

Supplement for iron deficiency/ anemia (oral):Doses ranging from 60 to 180mg of elemental iron have been used. Oral formulations of 325mg (60mg elemental iron) are usually taken by mouth with each meal three times daily. Liquid formulations of iron have shown a better bioavailability, with ferrous fumarate syrup and gelatin capsules being the most superior. A clinical trial demonstrated that an intensive dietary program instead of supplements has the potential to improve the iron status of women with iron deficiency. The diet included intake of flesh foods, heme iron, vitamin C and foods cooked using cast-iron cookware and significantly decreasing their phytate and calcium intakes. Please follow the guidance of a qualified healthcare provider when treating iron deficiency.

Dextran-iron (INFeD®) (injection): Dextran-iron is given by healthcare providers to replenish depleted iron stores in the bone marrow where it is incorporated into hemoglobin. Test dose: 0.5mL IV/IM (slowly over 1 minute if IV); observe for 60 minutes before providing additional medication. Usual adult dose: 2 mL/day (100mg iron); may be given until anemia is corrected.

Iron deficiency after gastrointestinal bleeding: A single dose of iron sucrose of 7 mg iron/kg body weight (not exceeding 500 mg) has infused over 3.5 hours in 31 consecutive patients with IDA due to gastrointestinal blood loss.

Iron deficiency anemia (IDA) in pregnancy (oral): An iron supplement of 20- 80mg/day from 18-20weeks of gestation has been shown to be adequate for preventing iron deficiency anemia with lower doses generally producing fewer side effects. Data on less frequent dosing is conflicting.

Depleted iron stores during pregnancy (postpartum) (oral): In one study, iron supplementation based on iron status early in pregnancy, with 60mg ferrous iron or 27mg iron containing heme, resulted in adequate iron stores at six weeks postpartum among 75% or 70% of the women, respectively. However, six weeks were not sufficient to rebuild iron stores in women with large peripartum blood loss.

Blood donors: 2000mg has been given intermittently over a period of two weeks after each blood-letting. It has been recommended that donations be limited to less than five per year or donors should regularly take an iron supplement to preserve reasonable amounts of iron reserves.

Pagophagia:The disappearance of pagophagia (compulsive eating of ice) after the correction of iron deficiency supports the theory that pagophagia could be a symptom of iron deficiency.

Hemodialysis: Nomograms may be useful for individualizing supplementary intravenous iron doses of iron for hemodialysis patients undergoing r-HuEPO therapy. In chronic hemodialysis patients, persistent low serum iron concentration may be an indication for iron supplements even though the serum ferritin concentrations are in the normal range. Iron requirements in hemodialysis patients must be determined by qualified healthcare providers.

Children (younger than 18 years):

Recommended Dietary Allowance (RDA): Infants 0-6 months 0.27 AI (adequate intake level (AI) used when RDA cannot be determined); 11mg for 7-12 months; 7mg for 1-3 years; 10mg for 4-8 years; 8mg for 9-13 years (male and female); 11mg for males 14-18 years; 15mg for females 14-18 years; 27mg for pregnant females 14-18 years; 10mg for breastfeeding females 14-18 years.

Tolerable Upper Intake Level (UL): Infants (1-12 months) not possible to establish; children (1-13 years) 40mg/day; adolescents (14-18 years) 45mg/day.

Prevention of iron deficiency:One case report suggests that premature infants who are formula fed should not receive iron supplements until they have doubled their birth weight or have a hemoglobin concentration of less than 10mg%. A total iron intake of 400micrograms/kg/day, half of which was provided by IV iron, was not sufficient to maintain iron balance or to meet fetal accretion rates (1000 micrograms/kg/day) in very-low-birth-weight newborns receiving total parenteral nutrition in once study. Endogenous iron from blood transfusions does not provide an adequate supply of iron. It has been shown that 2-month-old breast-fed infants are able to absorb nutritionally significant amounts of iron from an iron supplement. After five months of age exclusively breast-fed infants may be recommended to receive an additional 1mg/kg/day iron supplement and iron fortified formulas instead of fresh cow's milk during the first year of life. Appropriately iron-fortified weaning foods or the routine iron supplement starting at six months of age in exclusively breast-fed infants may also be recommended by some practitioners. In order to avoid iron deficiency, infants may continue to receive iron-fortified formula throughout the first year of life or a daily iron supplement if they are fed whole cow milk before their first birthday. Iron deficiency may protect against the development of febrile seizures. A specific feeding and supplement regimen should be recommended by a qualified healthcare provider.

Dextran-iron (INFeD®):INFeD® is anIntravenous preparation given by qualified healthcare provider toreplenish depleted iron stores in the bone marrow where it is incorporated into hemoglobin. Doses of 50mg iron (1mL) (5-10kg) and 100mg iron (2mL) (10-50kg) have been used.

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