What is the difference between intravenous (IV) iron dextran and iron sucrose for treating iron deficiency anemia?

Differences Between IV Iron Dextran and Iron Sucrose

IV iron sucrose is preferred over iron dextran for treating iron deficiency anemia due to its superior safety profile, as iron dextran carries a boxed warning for anaphylaxis risk requiring a test dose, while iron sucrose does not require a test dose and has fewer severe adverse reactions. 1, 2

Key Differences

Safety Profile

• Iron Dextran:

  • Carries a boxed warning regarding risk of anaphylactic reactions 1
  • Requires a test dose prior to full dose administration 1
  • Low molecular weight (LMW) iron dextran (Infed) is safer than the now discontinued high-molecular-weight formulation 1
  • Higher risk of hypersensitivity reactions compared to newer IV iron formulations 1

• Iron Sucrose:

  • No test dose required 1
  • Generally well-tolerated with fewer severe adverse reactions 3
  • Lower risk of anaphylaxis compared to iron dextran 4
  • Common side effects include dizziness, headache, hypertension, and injection-site reactions 2

Dosing and Administration

• Iron Dextran:

  • Can be given in doses >1000 mg by infusion 1
  • Lower cost compared to newer IV iron formulations 1
  • Typically administered as a total dose infusion 1

• Iron Sucrose:

  • Maximum individual dose of 200 mg per infusion 1, 2
  • Typically administered as slow intravenous infusion 1
  • May require multiple visits to achieve full iron repletion due to dose limitations 2
  • Can be safely administered at 200 mg weekly doses 3

Indications

• Iron Dextran:

  • Approved for treatment of iron-deficiency anemia unresponsive to oral iron therapy in both pediatric and adult patients 1
  • Broader approval for various types of iron deficiency anemia 1

• Iron Sucrose:

  • Initially approved specifically for use in patients with chronic kidney disease (CKD) and iron deficiency anemia 1
  • Now widely used across various conditions including inflammatory bowel disease, pregnancy, postpartum period, heavy menstrual bleeding, and cancer 5

Clinical Efficacy

Both iron dextran and iron sucrose demonstrate comparable efficacy in correcting anemia:

• Studies show that iron sucrose effectively increases hemoglobin levels by approximately 3.29 g/dL for women and 4.58 g/dL for men 3
• Response rates (defined as hemoglobin increase of at least 2 g/dL) are high with iron sucrose: 94% for male patients and 84% for female patients 3
• Both formulations effectively replenish iron stores, but iron sucrose shows better gastrointestinal tolerability in comparative studies 6

Practical Considerations

When to Consider Iron Dextran

• When total dose infusion is preferred (to minimize number of visits)
• When cost is a significant concern
• In patients with previous successful treatment with iron dextran without adverse reactions

When to Consider Iron Sucrose

• In patients at higher risk for hypersensitivity reactions
• When avoiding a test dose is preferred
• In patients with previous adverse reactions to iron dextran
• For patients with chronic kidney disease (specific indication)
• When multiple smaller doses are preferred over a single large infusion

Important Monitoring Considerations

• For both preparations, patients should be monitored for at least 30 minutes following administration 2
• Iron status should be re-evaluated 3 months after administration, as serum ferritin levels increase markedly following IV iron administration 2
• Target ferritin levels should be >100 μg/L and hemoglobin >12 g/dL 2

Pitfalls to Avoid

• Never administer iron dextran without first giving a test dose due to anaphylaxis risk 1
• Do not rely on ferritin levels as a reliable marker within 4 weeks of IV iron administration 2
• Do not exceed the maximum recommended single dose for each preparation (200 mg for iron sucrose) 1, 2
• Ensure administration is performed in settings where staff are trained to manage hypersensitivity reactions 2

High-dose iron sucrose protocols (up to 500 mg as a single dose) have been studied and appear safe in specific populations, but these exceed the standard approved dosing guidelines 7.