What is the appropriate dose of ferrous bisglycinate for a 5‑year‑old girl weighing 14.5 kg with iron‑deficiency anemia?

Ferrous Bisglycinate Dosing for Iron Deficiency Anemia in a 5-Year-Old Child

For a 5-year-old girl weighing 14.5 kg with iron deficiency anemia, prescribe 3 mg/kg/day of elemental iron as ferrous bisglycinate, which equals approximately 43.5 mg elemental iron daily, administered between meals for optimal absorption. 1

Dosing Calculation and Administration

• The Centers for Disease Control and Prevention recommends 3 mg/kg/day of elemental iron for treating iron deficiency anemia in children 1
• For this 14.5 kg child: 3 mg/kg × 14.5 kg = 43.5 mg elemental iron daily 1
• Administer the dose between meals (not with food or milk), as food reduces iron absorption by up to 50% 1
• Ferrous bisglycinate has demonstrated 90.9% bioavailability compared to 26.7% for ferrous sulfate, meaning lower doses may achieve equivalent therapeutic effect 2

Why Ferrous Bisglycinate Is Appropriate

• Ferrous bisglycinate chelate shows superior efficacy in increasing both hemoglobin and ferritin levels compared to polymaltose iron in pediatric studies 3
• The chelated form exhibits excellent tolerability with a low incidence of gastrointestinal side effects, improving adherence in young children 3, 2
• Research demonstrates that ferrous bisglycinate absorption is regulated by body iron demand, with greater uptake in children with lower baseline hemoglobin levels 3, 2
• One study showed ferrous bisglycinate significantly increased ferritin and mean corpuscular hemoglobin levels, while polymaltose iron did not 3

Treatment Duration and Monitoring

• Recheck hemoglobin after 4 weeks of therapy to confirm treatment response 1
• An increase of ≥1 g/dL hemoglobin (or ≥3% hematocrit) after 4 weeks confirms adequate response and validates the diagnosis of iron deficiency anemia 1
• Continue treatment for 2–3 months after hemoglobin normalizes to fully replenish iron stores 1
• Total treatment duration is typically 3–4 months from initiation 4

Dietary Counseling to Enhance Treatment

• Limit cow's milk intake to maximum 24 ounces daily, as excessive milk consumption is a major contributor to iron deficiency in children 1
• Encourage vitamin C-rich foods (citrus fruits, tomatoes, bell peppers) with iron doses to enhance absorption 5, 1
• Introduce iron-fortified cereals (two or more servings daily) and iron-rich foods such as meat, poultry, and fish 1
• Avoid administering iron with calcium-containing foods or supplements, as calcium interferes with iron absorption 5

Critical Pitfalls to Avoid

• Do not administer with meals or milk: This is the most common error that dramatically reduces bioavailability 1
• Do not discontinue prematurely: Stopping iron when hemoglobin normalizes fails to restore iron stores; the additional 2–3 months is essential 4, 1
• Monitor for iron overload with prolonged use: Although rare, amino acid chelated iron can cause secondary iron overload if used beyond one year without monitoring ferritin levels 6
• Check ferritin if treatment extends beyond 3–4 months: Even asymptomatic patients may develop iron accumulation with prolonged supplementation 6

When to Escalate Care

• If hemoglobin rises by <1 g/dL after 4 weeks despite documented adherence, obtain additional testing including mean corpuscular volume, red cell distribution width, and serum ferritin 4
• A serum ferritin ≥15 µg/L after inadequate response suggests an alternative etiology and warrants further investigation 4, 1
• Consider hematology referral if the cause of anemia remains unclear after extended testing or if there is no response to appropriate iron therapy 4

Practical Considerations

• Ferrous bisglycinate is available in liquid formulations suitable for young children, making administration easier than tablets 2
• The higher bioavailability of ferrous bisglycinate means that even if the child misses occasional doses, therapeutic effect is more likely maintained compared to conventional iron salts 2
• Side effects (nausea, constipation, dark stools) are significantly lower with ferrous bisglycinate than with ferrous sulfate, improving long-term adherence 3, 7