Iron

# Iron ## Overview - **Classification**: Mineral, Antianemic, Hematinic - **Mechanism**: Essential component of hemoglobin, myoglobin, and various enzymes. Facilitates oxygen transport and utilization, and cellular respiration. Corrects iron deficiency by replenishing stores. ## Primary Indications 1. **Iron Deficiency Anemia (IDA)**: Treatment and prevention. 2. **Iron Supplementation**: During pregnancy, lactation, rapid growth, or chronic blood loss. 3. **Restless Legs Syndrome**: If associated with iron deficiency. ## Adult Dosing ### Standard Dosing **Iron Deficiency Anemia (Treatment)** (Oral Iron) - **Dose**: **150-200 mg** elemental iron daily (e.g., **325 mg ferrous sulfate** contains **65 mg elemental iron**). - **Frequency**: Once daily to three times daily. - **Route**: Oral. - **Duration**: Usually 3-6 months after hemoglobin normalizes to replenish stores. **Iron Deficiency (Prevention/Supplementation)** (Oral Iron) - **Dose**: **30-60 mg** elemental iron daily. - **Frequency**: Once daily. - **Route**: Oral. - **Duration**: Ongoing as needed (e.g., pregnancy: **27 mg elemental iron** daily). ### Dose Adjustments - **Renal Impairment**: No specific oral iron adjustments. Parenteral iron may be preferred in CKD. - **Hepatic Impairment**: No specific oral iron adjustments. Avoid in hemochromatosis. - **Elderly Patients**: Start with lower doses due to potential for GI upset. Monitor for constipation. ## Pediatric Dosing ### Neonates (0-28 days) - **Indication**: Prevention of IDA in premature infants (<37 weeks gestation). - **Dose**: **2-4 mg/kg/day** elemental iron. - **Frequency**: Once daily. - **Maximum**: **15 mg/day**. - **Special Notes**: Initiate around 2-4 weeks of age. Use liquid formulation. Monitor for GI side effects. ### Infants (1-12 months) - **Indication**: Treatment of IDA. - **Dose**: **3-6 mg/kg/day** elemental iron, divided 1-2 times daily. - **Frequency**: Once or twice daily. - **Maximum**: **15 mg/day** (prevention), **50 mg/day** (treatment). - **Special Notes**: Use liquid formulation. Administer with vitamin C for absorption. ### Children (1-12 years) - **Indication**: Treatment of IDA. - **Dose**: **3 mg/kg/day** elemental iron, divided 1-2 times daily. - **Frequency**: Once or twice daily. - **Maximum**: **200 mg/day** elemental iron. - **Special Notes**: Chewable tablets or liquids available. Encourage administration with food if GI upset occurs. ### Adolescents (13-18 years) - **Indication**: Treatment of IDA. - **Dose**: **150-200 mg** elemental iron daily. - **Frequency**: Once to twice daily. - **Maximum**: **200 mg/day** elemental iron. - **Special Notes**: Adult dosing applies. Monitor for adherence and GI side effects. ## Safety Information ### Contraindications - **Absolute**: Hemochromatosis or hemosiderosis. - **Absolute**: Hemolytic anemia (unless iron deficiency also confirmed). - **Absolute**: Hypersensitivity to iron products. - **Relative**: Peptic ulcer disease, regional enteritis, ulcerative colitis (use oral with caution). ### Common Adverse Effects - **Very Common (>10%)**: GI upset (nausea, constipation, diarrhea), abdominal pain. - **Very Common (>10%)**: Darkening of stools (harmless). - **Common (1-10%)**: Heartburn, metallic taste (liquid formulations). - **Serious but Rare**: Iron toxicity (especially in children), anaphylaxis (with IV iron). ### Key Drug Interactions - **Tetracyclines/Quinolones**: Iron reduces absorption of antibiotics. Separate doses by **2-4 hours**. - **Levothyroxine**: Iron reduces absorption of thyroid hormone. Separate doses by **4 hours**. - **Antacids/PPIs/H2RAs**: Reduce iron absorption. Administer iron **2 hours before or 4 hours after** antacids. - **Vitamin C (Ascorbic Acid)**: Enhances iron absorption. Often co-administered. ## Monitoring & Follow-up - **Before Treatment**: Hemoglobin (Hgb), Hematocrit (Hct), Ferritin, Transferrin Saturation, CBC. - **During Treatment**: Hgb/Hct every **3-4 weeks** until normal, then Ferritin every **3 months** to confirm repletion. - **Clinical Signs**: Monitor for improvement in fatigue, pallor, and other anemia symptoms. Watch for GI side effects. ## Clinical Pearls - 💡 **Tip 1**: Administer oral iron on an empty stomach for best absorption (1 hr before or 2 hrs after meals). - 💡 **Tip 2**: If GI upset occurs, take with a small amount of food or try a different iron salt (e.g., ferrous gluconate). - 💡 **Tip 3**: Liquid iron can stain teeth; dilute and use a straw or dropper, then brush teeth. - 💡 **Tip 4**: Iron is a leading cause of poisoning in children; store in child-resistant containers, out of reach. > **⚠️ Important**: This information is for educational purposes only. Always consult current prescribing information, local guidelines, and clinical judgment before prescribing.