What is the typical dose of deferoxamine (iron chelator) for patients with iron overload due to blood transfusion-dependent anemia?

Deferoxamine Dosing for Transfusion-Dependent Anemia with Iron Overload

For patients with transfusion-dependent anemia and iron overload, administer deferoxamine subcutaneously at 20-50 mg/kg/day via continuous infusion over 8-12 hours for 5-7 days per week, with a typical total daily dose of approximately 2000 mg (40 mg/kg/day) for maximal urinary iron excretion. 1, 2

Standard Maintenance Dosing

• Subcutaneous administration is the preferred route for chronic iron chelation, delivered via portable infusion pump over 8-12 hours (typically overnight) at 20-50 mg/kg/day for 5-7 nights weekly 1, 2
• The dose of 40 mg/kg/day (approximately 2000 mg per 24 hours) typically achieves maximal urinary iron excretion in most patients 1
• Treatment frequency of 5-7 days per week is necessary to maintain negative iron balance and prevent progressive organ damage 1, 2

Intensive Dosing for Cardiac Iron Overload

When cardiac iron overload or heart failure is present, switch to continuous intravenous deferoxamine at higher doses (50-60 mg/kg/day) for rapid cardiac iron removal. 1, 2, 3

• Continuous IV infusion clears cardiac iron at nearly 5% per month, compared to only 1.1-2.2% per month with standard intermittent subcutaneous infusions 2
• For patients with depressed left ventricular ejection fraction and severe cardiac iron (T2* <20 ms), combination therapy with subcutaneous deferoxamine plus oral deferiprone 75 mg/kg/day for 7 days per week is superior to monotherapy 2, 4
• Cardiac stabilization may occur within 14 days but complete cardiac iron removal requires several years of continuous treatment 3

Monitoring Requirements

Target serum ferritin <1000 ng/mL during maintenance therapy, with monitoring every 3 months. 1, 3, 5

• Baseline and annual ophthalmologic and audiological examinations are mandatory due to risks of sensorineural deafness and visual disturbances, particularly at higher doses relative to iron burden 1, 2
• Annual cardiac T2* MRI starting at age 10 in transfusion-dependent patients to assess cardiac iron content 3, 5
• Annual liver iron concentration measurement by MRI 3, 5
• Growth monitoring in pediatric patients, as skeletal abnormalities and growth retardation can occur with excessive dosing 1, 2
• Weekly neutrophil monitoring if using combination therapy with deferiprone due to agranulocytosis risk 5, 6

Critical Dosing Pitfalls to Avoid

Never exceed infusion rate limits: acute respiratory distress syndrome can occur if the infusion rate exceeds 15 mg/kg/hr for the first 1000 mg, with subsequent dosing not exceeding 125 mg/hr. 2

• Excessive dosing relative to iron burden causes serious adverse events (ophthalmologic, audiological, skeletal abnormalities), particularly in pediatric patients 1, 2
• Avoid vitamin C supplementation, as pharmacological doses can accelerate iron mobilization beyond transferrin saturation capacity, resulting in increased pro-oxidant activity and risk of sudden death in patients with cardiac involvement 2
• Standard intermittent subcutaneous deferoxamine is relatively ineffective for cardiac iron clearance—if cardiac T2* is abnormal, either intensify to continuous IV administration or add deferiprone 2, 5
• Monitor for Yersinia and Klebsiella infections, which occur more frequently in deferoxamine-treated patients 1, 2
• Watch for renal toxicity, especially after high intravenous doses 1, 2

When to Consider Alternative or Combination Therapy

• Poor compliance with subcutaneous infusions undermines efficacy and places the heart at risk—consider switching to oral agents (deferasirox or deferiprone) if adherence is poor 2
• For patients with established cardiac iron overload (T2* <20 ms) or heart failure, deferiprone 75-100 mg/kg/day in three divided doses is superior to deferoxamine alone for cardiac iron clearance 5, 6
• Combination therapy with deferoxamine and deferiprone produces greater reductions in serum ferritin and improved left ventricular ejection fraction compared to monotherapy 4, 7
• Lifelong chelation is typically required in transfusion-dependent patients to prevent progressive iron accumulation 3, 5