Please note: this guideline has exceeded its review date and is currently under review by specialists. Exercise caution in the use of the clinical guideline.
This is an abbreviated version of the full guideline which is available on NHSAAA AthenA (link only active if accessing via NHS network). Otherwise, can be found via NHSAAA AthenA / Guidelines - Prescribing / Nutrition and Blood / Iron Deficiency Anaemia - treatment with intravenous iron (adults).
The guideline does not cover the diagnosis or treatment in the following clinical situations:
While oral iron preparations remain the first-line treatment for iron deficiency anaemia (IDA), the use of intravenous iron has become increasingly common in recent years. This guideline aims to inform the safe and appropriate use of these preparations in both inpatients and outpatients diagnosed with IDA, including haematology, gastroenterology and cardiology (heart failure) patients, as well as those undergoing surgical procedures and requiring peri-operative blood optimisation.
Iron deficiency develops over time when the body’s iron demand is not met by iron absorption. IDA occurs in the more severe stages of iron deficiency, when the body is iron deficient to the degree that red blood cell and haemoglobin (Hb) production is reduced.
The World Health Organisation defines anaemia as a Hb concentration of <130g/L in men aged >15 years and <120g/L in non-pregnant women aged >15 years. However, assessment of iron status is difficult and there is no single, ideal measurement. In addition, for patients undergoing surgery, it is important to optimise Hb preoperatively, with a target concentration of 130g/L for both men and women.
Measurement of serum ferritin and transferrin saturation (TSAT) should be undertaken to aid in the diagnosis of IDA. Note, however, that as ferritin is an acute phase protein it may sometimes be elevated even in the presence of functional iron deficiency if infection or inflammation are present.
Functional iron deficiency occurs when iron stores are adequate but there is insufficient mobilisation from iron stores in the presence of increased demand. This is characterised by:
Absolute iron deficiency occurs when iron stores are inadequate to support the erythropoietic needs of the bone marrow and is characterised by:
Patients with a serum ferritin <100micrograms/L should therefore be considered for iron supplementation. Patients diagnosed with absolute iron deficiency should also be referred for investigations to determine the underlying cause of this.
Oral iron supplementation is the first line treatment for IDA in adults. Prior to commencing any iron therapy, the underlying cause of iron deficiency should, as far as possible, be investigated, identified and treated. Other treatable causes of anaemia should also be excluded, including:
Any additional deficiencies detected should be corrected prior to commencing iron therapy. It is also important to be aware of the possibility of other haematological disorders (e.g. sideroblastic anaemia, myelodysplasia) as these are unlikely to respond to iron therapy.
Treatment with iron therapy (oral or parenteral) aims to attain haemoglobin levels of 130-150g/L, ferritin levels of 300-500micrograms/L and TSAT 20-40%. Note, however, that Hb should not exceed 120g/L in patients with severe cardiovascular disease (with the exception of heart failure patients as described above), peripheral vascular disease or diabetes unless angina symptoms dictate otherwise.
Give ferrous fumarate oral 210mg once a day.
Hb levels should rise by at least 20g/L over 3-4 weeks. Treatment should be continued for 3 months after Hb is optimised and then stopped.
If response is poor, consider:
*If oral iron treatment is not tolerated, adverse effects should be addressed by:
Iron salts are not well absorbed orally and their absorption is reduced if taken concurrently with certain foods/drugs/supplements such as:
Oral iron can reduce the absorption of some drugs if taken concurrently (including tetracyclines, quinolones and bisphosphonates) reducing bioavailability and clinical effect. A suitable interval to separate administration is advised.
Intravenous iron therapy can be considered in the following circumstances:
Intravenous iron therapy should be initiated by a consultant, specialist trainee or equivalent. Some services may delegate responsibility to nominated non-medical prescribers.
There can be complications with IV iron. See below for details. IV iron should not be administered out of hours or when adequate supervision is unavailable.
Cautions and contraindications to the use of intravenous iron include the following:
Cautions:
Refer to the individual Summaries of Product Characteristics (SPCs) for detailed information (available via www.medicines.org.uk).
Patients should also be advised to stop taking oral iron preparations 5 days prior to receiving IV iron. They should not receive oral and IV iron simultaneously.
Intravenous iron preparations should only be administered when staff trained to evaluate and manage anaphylactic reactions is immediately available, in an environment where full resuscitation facilities can be assured.
Use the treatment decision tool to guide product selection (as there are restrictions on the indications for which these may be used), then see the individual dosing and administration guides for:
Note: Prescribe on the Hospital Electronic Prescribing and Administration (HEPMA) system and a high risk infusion chart.
These include serious and potentially fatal anaphylactic / anaphylactoid reactions. Caution is needed with every dose of IV iron that is given, even if previous administrations have been well tolerated. Patients should be closely monitored for signs of hypersensitivity during, and for at least 30 minutes after every administration. If hypersensitivity reactions or signs of intolerance occur, the infusion must be stopped immediately. Further details are available in the full guideline on NHSAAA AthenA (link only active if accessing via NHS network).
Paravenous leakage at the infusion site may lead to irritation and potentially long lasting or permanent brown discolouration at the site of infusion. The most effective safeguard against extravasation is to visually inspect the infusion site regularly. Patients should be informed about the possibility of discolouration and advised to report any signs of irritation or pain at the infusion site. In case of suspected paravenous leakage the infusion must be stopped immediately. Further details are available in the full guideline on NHSAAA AthenA (link only active if accessing via NHS network).
Please refer to the individual manufacturers’ Summaries of Product Characteristics for full information. All intravenous iron products referred to in this guideline are black triangle (▼) drugs. As such, all adverse drug reactions to intravenous iron preparations should be reported to the Medicines and Healthcare products Regulatory Agency (MHRA) via the Yellow Card Scheme.
Hb and ferritin levels should be rechecked 4 weeks after treatment with IV iron to assess response to treatment.
| Guideline reviewed | February 2020 |
| Page updated | June 2026 |