Iron–Deficiency Anaemias

Prescribing Notes:

• Haemoglobin should rise by approximately 1–2g/litre (100mg to 200mg/100mL) per day or 20g/litre (2g/100mL) over 3 to 4 weeks. Once it has reached reference range, treatment should be continued for a further 3 months in order to replenish iron stores, and then stopped.

• Gastro-intestinal side-effects are common. Therefore although iron preparations are best absorbed on an empty stomach they may be taken after food to reduce these side-effects. If side-effects are problematic the dose can be reduced or an alternative preparation prescribed.

• Modified-release preparations have no therapeutic advantage and should not be used.

Prescribing Notes:

• Intravenous iron preparations can cause serious hypersensitivity reactions, including life-threatening and fatal anaphylactic and anaphylactoid reactions. See MHRA Drug Safety Update - Intravenous iron and serious hypersensitivity reactions: strengthened recommendations (December 2014).

• The only valid reason for administering iron parenterally is non-tolerance of oral therapy. If oral preparations are taken reliably and are absorbed, the haemoglobin response is not significantly faster with the parenteral route. In pre-operative patients who require optimisation of iron deficiency anaemia, intravenous iron may be first line if there is a short time frame to major surgery.

• Oral and parenteral iron should not be given at the same time and oral iron should not be restarted until 5 days after the parenteral dose has been given.

• Oral absorption in chronic renal impairment is poor and doesn’t work for functional iron deficiency which most of the haemodialysis patients have.

• Extravasation - paravenous leakage at the infusion site may lead to irritation of the skin and potentially long lasting brown discolouration at the site. Patients should be informed of the possibility of skin staining and advised to report any signs of irritation or pain at the infusion site immediately.