You’re asking about two specific injectable forms of iron: Iron Dextran and Iron Sorbitol Citrate complex, both at a concentration of 50 mg/mL. These are used when oral iron supplements are insufficient, not tolerated, or rapid iron repletion is required.
Here’s a breakdown of each:
(a) Iron Dextran Injection 50 mg/mL
Description
Iron Dextran Injection 50 mg/mL is a sterile, dark reddish-brown colloidal solution containing a complex of ferric hydroxide and dextran. This formulation provides 50 mg of elemental iron per milliliter. It is administered intravenously (IV) or intramuscularly (IM) and is used to treat iron deficiency anemia in patients who cannot tolerate or adequately absorb oral iron, or who have severe, ongoing blood loss.
Advantages
- Effective for Severe Deficiency: Ideal for rapid and significant repletion of iron stores in severe iron deficiency anemia.
- Alternative to Oral Iron: Provides a crucial option for patients who experience severe gastrointestinal side effects from oral iron, or who have malabsorption conditions (e.g., inflammatory bowel disease, gastric bypass).
- Reduces Transfusion Needs: Can reduce the need for red blood cell transfusions in certain patient populations.
- Convenient Dosing: Allows for administration of a large total dose of iron in one or a few sessions, compared to daily oral therapy.
Uses
Iron Dextran Injection 50 mg/mL is primarily used for the treatment of:
- Iron Deficiency Anemia: In patients with documented iron deficiency where oral iron therapy is ineffective, not tolerated, or contraindicated. This includes:
- Patients with chronic blood loss (e.g., hereditary hemorrhagic telangiectasia).
- Patients with malabsorption syndromes (e.g., Crohn’s disease, celiac disease).
- Patients on hemodialysis receiving erythropoietin.
- Post-surgical iron deficiency.
- Iron Replacement: To replenish iron stores lost due to significant blood loss.
Nature
Iron Dextran is a colloidal complex of ferric hydroxide (Fe$^{3+}$) and dextran, a polysaccharide.
Its mechanism of action involves:
- Absorption and Uptake: After IV or IM administration, the iron dextran complex is removed from the bloodstream by cells of the reticuloendothelial system (RES), primarily macrophages in the liver, spleen, and bone marrow.
- Iron Release: Within the RES cells, the complex is broken down, and elemental iron is gradually released from the dextran component.
- Binding and Transport: The released iron then binds to transferrin, the body’s iron-transport protein. Transferrin carries the iron to the bone marrow.
- Hemoglobin Synthesis: In the bone marrow, the iron is incorporated into hemoglobin within developing red blood cells, leading to increased red blood cell production and correction of anemia.
- Storage: Excess iron is stored as ferritin or hemosiderin, replenishing the body’s iron reserves.
A key aspect of Iron Dextran’s nature is the strong complex, which ensures a slow and controlled release of iron, minimizing the risk of free iron toxicity. However, the dextran component has historically been associated with a higher risk of anaphylactic reactions compared to newer IV iron preparations, necessitating a test dose for some formulations or careful monitoring.
Storage
- Room Temperature: Store Iron Dextran Injection 50 mg/mL at controlled room temperature, typically between 20∘C to 25∘C (68∘F to 77∘F).
- Protect from Light: Keep the vials or ampoules in their original carton to protect them from light.
- Do Not Freeze: Freezing can compromise the integrity of the colloidal solution.
- Single-Dose Vial: Most presentations are for single-dose use. Any unused portion should be discarded immediately after drawing the dose, as they typically do not contain preservatives.
- Keep Out of Reach of Children: Store securely, away from children and unauthorized individuals.
- Check Expiry Date: Always check the expiry date on the packaging. Do not use the injection beyond this date.
(b) Iron Sorbitol Citrate Complex Injection 50 mg/mL
Description
Iron Sorbitol Citrate Complex Injection 50 mg/mL is a sterile colloidal solution containing ferric iron complexed with sorbitol and citric acid. This formulation provides 50 mg of elemental iron per milliliter. Historically, this type of iron complex was primarily administered intramuscularly (IM), though some newer formulations or uses might explore IV routes under strict supervision. It’s used to treat iron deficiency anemia when oral iron is insufficient, poorly tolerated, or rapid iron repletion is needed.
Advantages
- Effective Iron Repletion: Supplies elemental iron directly into the bloodstream to correct iron deficiency anemia.
- Alternative to Oral Iron: Useful for patients unable to tolerate or absorb oral iron.
- Rapid Correction: Can lead to a quicker increase in hemoglobin levels compared to oral iron, particularly in severe cases.
Uses
Iron Sorbitol Citrate Complex Injection 50 mg/mL is primarily used for the treatment of:
- Iron Deficiency Anemia: In patients where oral iron is unsuitable, ineffective, or when a rapid response is required. This often includes:
- Chronic kidney disease patients.
- Patients with malabsorption syndromes.
- Patients with chronic blood loss.
- Pre- and post-operative iron therapy.
Nature
Iron Sorbitol Citrate Complex is a colloidal solution of ferric iron (Fe$^{3+}$) complexed with sorbitol and citric acid.
Its mechanism of action involves:
- Direct Systemic Delivery: When administered (historically IM, though formulation-dependent), the complex delivers iron directly into the systemic circulation, bypassing the gastrointestinal tract.
- Iron Release and Transport: The iron is gradually released from the complex. It then binds to transferrin for transport to the bone marrow and other sites where iron is needed.
- Hemoglobin Synthesis: In the bone marrow, iron is incorporated into hemoglobin, stimulating red blood cell production.
- Storage: Any excess iron is stored in the body’s iron reserves (ferritin, hemosiderin).
Compared to iron dextran, iron sorbitol citrate complex has a smaller molecular size, which historically led to faster absorption from the injection site. However, it was also associated with a higher risk of local staining at the injection site (brown discoloration of the skin) and potential for transient dark urine. Newer IV iron formulations are generally preferred over this complex due to better safety profiles and ease of administration.
Storage
- Cool, Dry Place/Room Temperature: Store Iron Sorbitol Citrate Complex Injection at controlled room temperature, typically between 20∘C to 25∘C (68∘F to 77∘F), unless specific manufacturer instructions dictate otherwise. Some sources may recommend a cool, dry place away from direct sunlight.
- Protect from Light: Keep the ampoules or vials in their original packaging to protect from light.
- Do Not Freeze: Freezing can damage the solution.
- Single-Dose Vial: Typically supplied in single-dose containers. Any unused portion should be discarded after use.
- Keep Out of Reach of Children: Store securely, away from children and unauthorized individuals.
- Check Expiry Date: Always check the expiry date and do not use the injection beyond this date.