Contraindications for Monofer (Iron Isomaltoside-1000)
Monofer is absolutely contraindicated in patients with hypersensitivity to the active substance or any excipients, known serious hypersensitivity to other parenteral iron products, anemia not due to iron deficiency, and evidence of iron overload or disturbances in iron utilization. 1
Absolute Contraindications
Hypersensitivity reactions: Do not administer to patients with known hypersensitivity to iron isomaltoside-1000, any of its excipients, or documented serious hypersensitivity to other parenteral iron formulations 1, 2
Non-iron deficiency anemia: Contraindicated in patients with anemia not attributed to iron deficiency, such as other microcytic anemias (e.g., thalassemia, sideroblastic anemia) 1, 2
Iron overload: Do not use in patients with evidence of iron overload (elevated ferritin with high transferrin saturation) or disturbances in iron utilization 1, 2, 3
Ongoing bacteremia: Treatment must be stopped immediately in patients with active bacteremia 1, 2
High-Risk Situations Requiring Extreme Caution
Infection-Related Concerns
Acute or chronic infection: Use with extreme caution in patients with active infections, though infection alone should not be considered an absolute contraindication if the risk-benefit assessment favors treating the anemia 1
Withhold administration in patients with ongoing bacteremia until infection is controlled 1, 2
Hypersensitivity Risk Factors
Patients at significantly increased risk for hypersensitivity reactions include those with: 1, 2, 4, 5
- Previous hypersensitivity reaction to any intravenous iron preparation
- Multiple drug allergies
- Severe asthma, eczema, or other atopic allergies
- Immune or inflammatory conditions (systemic lupus erythematosus, rheumatoid arthritis)
- High serum tryptase levels
Important note: Monofer (iron isomaltoside-1000) has been associated with higher hypersensitivity reaction rates (8.7%) compared to ferric carboxymaltose (2.1%), with a 3.4-fold increased likelihood of reactions 6. Patients with comorbidities have a 3.6-fold higher risk of hypersensitivity reactions regardless of iron preparation used 6.
Special Populations
Early pregnancy: Contraindicated in early pregnancy; intravenous iron should be avoided during the first trimester 4
Pediatric patients: Safety and efficacy not established in children under 2 years of age 1
Hemoglobin >15 g/dL: Efficacy and safety have not been evaluated in patients with hemoglobin levels exceeding 15 g/dL 1, 2
Critical Safety Monitoring Requirements
All patients must be observed for at least 30 minutes following each intravenous injection, as hypersensitivity reactions can occur up to 30 minutes post-administration. 1, 2, 3
Emergency Preparedness
Administer only where personnel and therapies are immediately available for treating serious hypersensitivity reactions, including anaphylaxis 3
If hypersensitivity or signs of intolerance occur, stop the infusion immediately 3
Have epinephrine, antihistamines, and hydrocortisone readily available 3, 4
Administration Precautions
Ensure stable intravenous access to avoid extravasation, which can cause injection site discoloration 3
Avoid rapid infusion rates, as this increases hypersensitivity risk 4, 5
Monitor for hypotension during and after administration, as clinically significant hypotension may occur 3
Monitoring for Iron Overload
Periodically monitor hemoglobin, hematocrit, serum ferritin, and transferrin saturation in all patients receiving Monofer 3
Do not perform serum iron measurements for at least 48 hours after intravenous dosing, as transferrin saturation values increase rapidly after administration 3
Excessive therapy can lead to hemosiderosis; discontinue if iron overload develops 3