Ferumoxytol (Feraheme) Infusion Duration
Ferumoxytol must be administered as an intravenous infusion over at least 15 minutes, not as a rapid injection. 1
Standard Administration Protocol
The FDA-approved dosing regimen is 510 mg infused over at least 15 minutes, followed by a second 510 mg dose 3-8 days later. 1 This represents a critical change from the original rapid injection method that led to unacceptably high rates of hypersensitivity reactions. 2
Preparation and Infusion Details
- Dilute ferumoxytol in 50-200 mL of either 0.9% sodium chloride or 5% dextrose solution (concentration of 2-8 mg elemental iron per mL). 1
- Administer the infusion with the patient in a reclined or semi-reclined position. 1
- The diluted solution should be used immediately but may be stored at room temperature for up to 4 hours or refrigerated for up to 48 hours. 1
Critical Safety Monitoring Requirements
Personnel and therapies for treating anaphylaxis must be immediately available during every ferumoxytol infusion. 1 This is non-negotiable given the risk of fatal hypersensitivity reactions.
Monitoring Protocol
- Monitor blood pressure and pulse continuously during the infusion and for at least 30 minutes after completion until the patient is clinically stable. 1
- Hypersensitivity reactions can occur even in patients who previously tolerated ferumoxytol without incident. 1
- Allow at least 30 minutes between ferumoxytol and any other medications that could cause hypersensitivity reactions or hypotension (chemotherapy agents, monoclonal antibodies). 1
Evidence Supporting Slower Infusion
The American Society of Hematology notes that when ferumoxytol was initially approved for rapid injection, it resulted in high rates of infusion reactions that were often misinterpreted as anaphylaxis. 2 Using the slower 15-minute infusion method, serious adverse events are "vanishingly rare" with minor infusion reactions occurring at only 1-3% incidence, equivalent to other IV iron formulations. 2
Alternative Single-Dose Regimen
Research has demonstrated that 1,020 mg (two vials) can be safely administered as a single 30-minute infusion in selected patients, though this is not FDA-approved. 2, 3 In a study of 60 patients with iron deficiency anemia, this approach showed no serious adverse events and excellent efficacy. 3 However, the FDA-approved labeling requires the two-dose regimen separated by 3-8 days. 1
Special Populations
For hemodialysis patients, administer ferumoxytol only after blood pressure is stable and the patient has completed at least one hour of dialysis. 1 Monitor closely for hypotension following each infusion in this population. 1
Important Caveat: MRI Interference
Ferumoxytol is a superparamagnetic iron oxide that can affect MRI interpretation for up to 3 months after administration—radiologists must be notified if MRI is planned within this timeframe. 2
Response Assessment
Evaluate hemoglobin, ferritin, iron, and transferrin saturation at least one month following the second infusion. 1 The dose may be readministered to patients with persistent or recurrent iron deficiency anemia. 1