1. Clinical Overview
Iron (200mg) typically refers to elemental iron supplied as a salt (e.g., Ferrous Ascorbate, Ferrous Fumarate, Ferrous Sulphate) for oral administration. It is a critical hematinic agent used to treat and prevent iron deficiency states. In the Indian context, it is widely prescribed due to the high prevalence of nutritional anemias, especially among women of childbearing age, pregnant women, and children. The 200mg dose usually refers to the total salt content, with the elemental iron content varying by salt (e.g., ~65mg elemental iron from 200mg Ferrous Ascorbate).
| Onset | Duration | Bioavailability |
|---|---|---|
| Reticulocyte count begins to increase in 5-10 days. Hemoglobin levels typically start rising within 2-4 weeks of initiation. | Duration is dependent on the correction of the underlying deficiency and continued replenishment of body stores. Effects persist as long as adequate iron levels are maintained. | Approximately 5-15% in iron-deficient individuals, significantly lower (1-2%) in iron-replete states. Absorption is highly variable and influenced by dietary factors, gastric pH, and formulation. |
2. Mechanism of Action
Iron is an essential component of hemoglobin, myoglobin, and various enzymes (e.g., cytochromes, catalase, peroxidase). In iron deficiency anemia, it replenishes depleted iron stores, allowing for the normal synthesis of hemoglobin in erythroid precursor cells in the bone marrow, thereby increasing the oxygen-carrying capacity of blood.
3. Indications & Uses
- Iron Deficiency Anemia (Microcytic Hypochromic Anemia)
- Prophylaxis of Iron Deficiency in high-risk groups (pregnancy, chronic blood loss, malnutrition)
4. Dosage & Administration
Adult Dosage: For treatment of IDA: 100-200 mg of elemental iron per day, in 2-3 divided doses. A common regimen is Ferrous Ascorbate 200mg tablet (providing ~65mg elemental iron) twice daily. For prophylaxis: 30-60 mg elemental iron daily.
Administration: Take on an empty stomach (1 hour before or 2 hours after meals) for maximum absorption. If GI upset occurs, take with a small amount of food (avoid dairy, cereals, tea, coffee, antacids which inhibit absorption). May be taken with Vitamin C (ascorbic acid) or orange juice to enhance absorption. Do not crush or chew sustained-release formulations. Swallow whole with a full glass of water.
5. Side Effects
Common side effects may include:
- Nausea, Epigastric discomfort
- Constipation (more common) or Diarrhea
- Black or dark green stools (harmless)
- Abdominal pain
- Heartburn
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Antacids (Aluminum, Magnesium, Calcium salts) | Decreased absorption of iron due to increased gastric pH and formation of insoluble complexes. | Major |
| Tetracyclines, Fluoroquinolones (Ciprofloxacin, Levofloxacin) | Decreased absorption of both iron and the antibiotic due to chelation. Administer at least 2-3 hours apart. | Major |
| Levothyroxine | Decreased absorption of levothyroxine. Administer at least 4 hours apart. | Major |
| Bisphosphonates (Alendronate) | Decreased absorption of bisphosphonate. Administer at least 30-60 minutes apart. | Moderate |
| Chloramphenicol | Delayed iron response due to bone marrow suppression. | Moderate |
| Vitamin C (Ascorbic Acid) | Increased absorption of non-heme iron. | Minor (Beneficial) |
| Penicillamine | Decreased absorption of penicillamine. | Moderate |
| Methyldopa | Potential decreased absorption and efficacy of methyldopa. | Moderate |
7. Patient Counselling
- DO take on an empty stomach for best absorption.
- DO take with a source of Vitamin C (orange juice, ascorbic acid tablet) if tolerated.
- DO report severe constipation, abdominal pain, or black tarry stools (melena) to your doctor.
- DON'T take with antacids, calcium supplements, tea, coffee, or dairy products within 2 hours.
- DON'T crush or chew sustained-release tablets.
- DO keep all iron supplements out of reach of children - they look like candy and are a leading cause of fatal pediatric poisoning.
- DO complete the full course as prescribed, even after you feel better, to replenish iron stores.
8. Toxicology & Storage
Overdose: Acute (within 6 hrs): Nausea, vomiting (often bloody), abdominal pain, diarrhea, lethargy. Stage 2 (6-24 hrs): Apparent recovery. Stage 3 (12-48 hrs): Metabolic acidosis, hypoglycemia, coagulopathy, shock, hepatic failure, renal failure, seizures, coma. Stage 4 (2-5 days): GI scarring/pyloric stenosis.
Storage: Store in a cool, dry place below 30°C. Protect from light and moisture. Keep the container tightly closed. Keep out of reach and sight of children. Do not use after the expiry date printed on the pack.