Iron Supplementation Dose for a 10.9 kg Child with Ferritin 21 ng/mL
For this 10.9 kg child with a ferritin of 21 ng/mL, administer approximately 33 mg of elemental iron daily (3 mg/kg/day), given as ferrous sulfate drops between meals. 1, 2
Dosing Calculation
The standard therapeutic dose for treating presumptive iron-deficiency anemia in infants and young children is 3 mg/kg per day of elemental iron 1, 2
For a 10.9 kg child: 10.9 kg × 3 mg/kg = 32.7 mg elemental iron daily (round to 33 mg) 2
Using ferrous sulfate drops (25 mg elemental iron per mL), this equals approximately 1.3 mL daily 2
Interpretation of Ferritin Level
A ferritin of 21 ng/mL in a child is not definitively iron-deficient by strict laboratory criteria (typically <15 μg/L confirms deficiency), but falls in a borderline range that warrants treatment if anemia is present 1, 3
The decision to treat should be based on hemoglobin/hematocrit values in addition to ferritin, as ferritin alone at this level does not confirm iron-deficiency anemia 1
If hemoglobin is low for age, proceed with presumptive treatment at 3 mg/kg/day 1, 2
Administration Guidelines
Give iron between meals (on an empty stomach) to maximize absorption, as food can reduce iron bioavailability by up to 50% 2, 4
Specifically, administer at least 2 hours before or 1 hour after meals 4
Avoid giving with milk, tea, coffee, or dairy products, which significantly inhibit iron absorption 4
Treatment Duration and Monitoring
Continue initial therapy for 4 weeks, then recheck hemoglobin or hematocrit 1, 2
An increase of ≥1 g/dL in hemoglobin (or ≥3% in hematocrit) after 4 weeks confirms iron-deficiency anemia and indicates treatment is working 1, 2
If response is confirmed, continue treatment for 2 additional months (total ~3 months) to replenish iron stores 1, 2
Recheck hemoglobin after completing the full course, with follow-up assessment approximately 6 months later 1, 2
Management of Non-Response
If anemia does not improve after 4 weeks despite confirmed adherence and absence of acute illness, obtain additional laboratory tests: MCV, RDW, and repeat serum ferritin 1, 2
A serum ferritin <15 μg/L confirms iron deficiency; >15 μg/L suggests another cause of anemia 1
Consider malabsorption, ongoing blood loss, or concurrent nutritional deficiencies (B12, folate) if no response occurs 2, 4
Dietary Counseling
Provide concurrent dietary counseling to address underlying inadequate iron intake, which is the root cause in most pediatric iron deficiency 1, 2
Encourage iron-rich foods and foods that enhance iron absorption (vitamin C-containing fruits and vegetables) 1
Common Pitfalls
Do not use adult dosing regimens (such as 60 mg tablets twice daily) in children—pediatric dosing must be strictly weight-based 2
Mild gastrointestinal symptoms (nausea, constipation) are common but should not prompt immediate discontinuation; consider dividing the dose or giving with small amounts of food if intolerable 2, 4
Avoid excessive dosing: systemic iron toxicity with hepatocellular damage has been reported in pediatric patients receiving excessive iron 1, 2