๐ About IV Iron
- Used to treat iron deficiency anaemia when oral iron is ineffective, not tolerated, or contraindicated (e.g. IBD, CKD, perioperative optimisation).
- Earlier formulations (e.g. high-molecular weight iron dextran) had higher risk of anaphylaxis. โ
Newer agents (iron sucrose, ferric carboxymaltose) are safer but reactions can still occur.
- โ ๏ธ IV iron should always be administered in a setting with immediate resuscitation facilities and staff trained in managing anaphylaxis.
๐จ Warnings
- ๐ Monitor all patients during infusion and for at least 30 min afterwards.
- โ Test doses are no longer recommended (reaction can still occur at any time).
- โ ๏ธ Allergic reactions more common with iron dextran โ consider switching to sucrose or carboxymaltose if reaction occurs.
- Large total doses (iron dextran, ferric carboxymaltose) can be given in one sitting; others (iron sucrose, gluconate) require divided doses.
๐ Common IV Iron Preparations
- Iron Dextran (Cosmofer)
- IV infusion in 5% glucose or 0.9% saline.
- Initial: 25 mg over 15 min โ then max 6.7 mg/min.
- Total dose infusion: 100โ200 mg diluted, over 4โ6 hrs.
- Iron Sucrose (Venofer)
- IV infusion in 0.9% saline.
- Start with 25 mg test infusion over 15 min.
- Max 100 mg per dose, diluted in 100 mL.
- Ferric Carboxymaltose (Ferinject)
- Given IV via infusion pump.
- Max: 1000 mg (โค20 mg/kg).
- Faster infusion, fewer visits compared to sucrose.
- Ferric Derisomaltose (Monofer)
- Allows large single dose infusions (up to 20 mg/kg).
- Useful in CKD and perioperative anaemia optimisation.
โก Side Effects
- Allergic: Anaphylaxis, urticaria, angioedema, bronchospasm.
- Common: Flushing, dizziness, nausea, headache, hypotension or hypertension, metallic taste, hypophosphataemia.
- Local: Pain, irritation, brown skin staining if extravasation (esp. with Ferinject).
๐ ๏ธ Management of Side Effects
- ๐ธ Mild reaction: Stop infusion, monitor, give IV antihistamines ยฑ hydrocortisone.
- ๐จ Severe / Anaphylaxis:
- Stop infusion immediately.
- Call for help โ follow ABC protocol.
- High-flow oxygen + IV fluids.
- Adrenaline IM (0.5 mg 1:1000) โ repeat every 5 min if needed.
- IV hydrocortisone (100 mg) + IV chlorphenamine (10 mg).
- Prepare for airway/ITU support if refractory.
- ๐ Extravasation: Stop infusion, elevate limb, apply cold compress. Warn about possible permanent staining.
๐ Clinical Pearls
- Check ferritin, iron studies, Hb before starting therapy.
- Use local guidelines or calculators for iron dose requirement (based on weight + Hb deficit).
- ๐ก CKD patients: IV iron often used alongside ESAs (erythropoiesis-stimulating agents).
- ๐ซ Avoid unnecessary IV iron in patients with ferritin >800 ยตg/L or active sepsis.
๐ Take-home: IV iron is highly effective and safe with modern formulations, but rare life-threatening reactions demand vigilance.
Always infuse in resus-ready environment and reassess response after 4โ8 weeks.