Oral Iron Supplementation for a 2-Year-Old with ARFID and Iron-Deficiency Anemia
Prescribe ferrous sulfate drops at 3 mg/kg/day of elemental iron (36 mg/day for this 12 kg child), administered as a single morning dose between meals with vitamin C-rich juice, and reassess hemoglobin after 4 weeks. 1
Formulation and Dosing
Use ferrous sulfate drops as the first-line oral iron preparation—it remains the most cost-effective and efficacious option for treating iron-deficiency anemia in young children. 2, 3
Calculate the dose at 3 mg/kg/day of elemental iron, which equals 36 mg/day for this 12 kg child. 1 This dosing range (3–6 mg/kg/day) optimally corrects anemia without excessive gastrointestinal side effects. 2
Administer the entire daily dose once in the morning rather than splitting it throughout the day. Recent evidence shows single morning doses maximize fractional iron absorption compared to divided or afternoon dosing. 4, 5
Timing and Co-Administration
Give the dose between meals—specifically, at least 1–2 hours away from food—because concurrent food intake reduces non-heme iron absorption by up to 50%. 1, 5
Pair the iron dose with vitamin C-rich juice (e.g., orange juice containing ~80–90 mg ascorbic acid) to enhance absorption by approximately 30%. 1, 5 Avoid coffee or tea, which decrease absorption by more than 50%. 5
Avoid administering iron with or immediately after cow's milk, and limit total milk intake to less than 24 oz/day, as excessive milk consumption is a recognized risk factor for iron deficiency in toddlers. 1
Monitoring and Response Assessment
Recheck hemoglobin after 4 weeks to assess therapeutic response. 1 A positive response is defined as a hemoglobin increase of ≥1 g/dL (or hematocrit rise ≥3%). 1
If the response is adequate, continue iron supplementation for an additional 2 months (approximately 3 months total) to fully replenish iron stores. 1
Perform a final hemoglobin check at the end of the 3-month course and schedule repeat screening about 6 months later to ensure sustained adequacy. 1
Management of Non-Response
If hemoglobin fails to rise by ≥1 g/dL after 4 weeks, obtain mean corpuscular volume (MCV), red-cell distribution width (RDW), and repeat ferritin to explore alternative causes. 1
A repeat ferritin ≤15 µg/L confirms persistent iron deficiency and suggests poor compliance, malabsorption, or ongoing blood loss. 1 A ferritin >15 µg/L points toward other etiologies such as thalassemia trait, chronic inflammation, or lead exposure. 1
In cases of confirmed malabsorption or intolerance to oral iron, consider intravenous iron therapy. Iron sucrose is the most studied IV preparation in children and is FDA-approved for pediatric use from 2 years of age. 6
Practical Considerations for ARFID
Given the feeding restrictions of ARFID, work with the family to identify a tolerated vitamin C-rich beverage (orange juice, fortified apple juice, or diluted lemon water) that the child will accept alongside the iron drops. 1, 5
Mild gastrointestinal side effects (nausea, constipation, dark stools) are common but should not lead to discontinuation unless severe. 6, 1 Reassure caregivers that these effects often diminish with continued use.
Do not delay treatment while waiting for hemoglobin to drop further; even with a ferritin of 21 µg/L and normal hemoglobin, iron stores are already depleted and warrant immediate supplementation. 1
Avoid over-supplementation once stores are replete, as excessive iron can impair growth and disrupt gut microbiota. 1