Oral Iron Therapy
- Is safe, cost-effective, convenient, well tolerated.
- Given empty stomach or in between meals.
- Ferrous salts are preferred as they are better absorbed than ferric forms.
- New iron preparations: Not affected by the dietary factors, and have less gastrointestinal side effects (iron polymaltose complex, iron amino acid chelates, carbonyl iron, Ferrous ascorbate and ferrous bisglycinate).
- The recommended dosage of elemental iron is 3 mg/kg/day. Single daily doses are as effective, but 2–3 divided doses are better tolerated by children.
- Therapy continued for at least 2-3 months after Hb becomes normal, to replenish iron stores.
Dietary Factors that Enhance and Inhibit Iron Absorption
| Enhance | Inhibit |
|---|---|
| Meat | Phosphate |
| Fish | Calcium |
| Poultry | Tea (Tannic acid) |
| Seafood | Coffee |
| Gastric acid | Cola |
| Ascorbic acid | Soy protein |
| Malic acid | High doses of minerals |
| Citric acid | Bran/fiber |
Sequence of Events After Iron Therapy in IDA
| Time After Iron Administration | Development |
|---|---|
| 2-24 hrs | Replacement of intracellular iron enzymes, subjective improvement, decreased irritability and increased appetite. |
| 24-48 hrs | Initial bone marrow response, erythroid hyperplasia. |
| 48-72 hrs | Reticulocytosis peaking at 5-7 days. |
| 4-30 days | Increase in Hb level. |
| 1-3 months | Repletion of stores. |
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Pica, Pagophagia and non-specific symptoms disappear within one week.
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Epithelial lesions affecting tongue and nails respond to treatment after 2 weeks of therapy.
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Koilonychia disappear within 3-6 months.
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A positive response is considered when there is a daily rise in the Hb concentration of 0.1 g/dl from the fourth day onwards.
Major Side Effects of Oral Iron Therapy
- Heartburn
- Nausea
- Vomiting
- Abdominal cramps
- Diarrhea
- Constipation
- Staining of tongue and teeth
- Blackish discoloration of stools
- Rarely acute iron poisoning and death
Absorption of 60mg/kg is probably necessary for the development of significant iron poisoning.
Failure to Respond to Oral Iron Therapy
- Wrong Diagnosis
- Poor compliance
- Discontinuation of treatment
- Selection of preparation with poor absorption of iron
- Adverse symptoms: constipation, diarrhea, heartburn, and abdominal cramps
- Malabsorption due to GIT disease
- Loss at a greater rate – chronic bleeding
Recommended Guidelines for Preventing and Treating Iron Deficiency Anemia in Infants and Children
| Group | Iron Supplementation Recommendations |
|---|---|
| Term, Breastfed Infants | 1 mg/kg/day of supplemental iron starting at age 4 months until introduction of supplementary food. After weaning from breast, stop supplemental iron; use iron-fortified infant formula until age 12 months. Avoid cow’s milk until after age 12 months. |
| Term, Formula Fed Infants | Use iron-fortified infant formula until age 12 months. Avoid cow’s milk until after age 12 months. |
| Preterm Infants | 2 mg/kg/day of supplemental iron or iron-fortified formula no later than age 1 month and continue to age 12 months. |
| Children | 3-6 mg/kg/day |
| Adolescents | 60 mg/dose |
Parenteral Iron Therapy
- Parenteral iron is not superior to oral iron.
- Therapy is more expensive and risky than oral therapy.
Indications for parenteral iron therapy:
- Oral iron is poorly tolerated
- Rapid replacement of iron stores
- Malabsorption
This includes both IM and IV. Three IV forms available: iron dextran, iron gluconate, iron sucrose.
Total dose of elemental iron [mg] = wt [kg] Ă— Hb deficit [g/dl] Ă— 4.
Side effects include pain, flushing, pyrexia, malaise, vomiting, chills, arthralgia, anaphylaxis.