Dr Cory Dugan

Iron infusions and doctor reluctance

In 2024, one in 20 Australian women aged 18 to 44 was dispensed intravenous iron. A doctor's caution about infusions has specific reasons, and knowing them makes the conversation more productive.

By Dr Cory Dugan, PhD. Published September 2026.

Oral iron is slow to rebuild stores, and its side effects, including nausea, abdominal pain and constipation, mean many people struggle to keep taking it. An infusion aims to replace iron stores in a single sitting.

This page sets out the case for your doctor's caution, then the case against it, then the situations where an infusion is a reasonable thing to ask for.

Intravenous iron dispensing in Australia, 2013 to 2024

A 2026 analysis of Pharmaceutical Benefits Scheme dispensing data tracked intravenous iron among Australian women aged 18 to 44. In 2013, 0.3 in every 100 women were dispensed it. By 2024 that had risen to 5.0 in every 100, or one woman in 20, and total spending on the medicine alone rose from $1.1 million to $82.3 million.

A community screening study of 640 women of reproductive age in Western Australia found that a history of iron infusion was common.

The authors of the national analysis also found more than threefold variation in use between states and territories, and concluded that the rapid rise and the degree of variation raise questions about whether intravenous iron is being prescribed appropriately and cost-effectively.

Reason 1: oral iron as first-line treatment

Australian Prescriber describes oral iron as the first-line and safest treatment for iron deficiency, and says most people with iron deficiency can be given oral supplements. Iron studies are then repeated after 60 to 90 days to see whether it has worked.

A separate Australian Prescriber article states that intravenous iron is usually only indicated when oral iron has failed, and that an infusion is rarely urgent.

A general practitioner (GP) who suggests tablets first is following the documents they are expected to follow. Whether the tablets were given a fair trial is covered in why your iron tablets aren't raising your ferritin.

Reason 2: the side effects of intravenous iron

Australian Prescriber states that the use of intravenous iron should be limited because of three adverse effects in particular: permanent skin staining, low blood phosphate, and rarely anaphylaxis.

Low phosphate after the infusion

Some intravenous iron products cause the kidneys to excrete more phosphate, which lowers the level in the blood. Concern about this has grown from reports of osteomalacia, a softening of bone, and fractures. The effect depends heavily on which product is used.

StudyWhat it found
Meta-analysis of 42 clinical trials, 2021Hypophosphataemia in 47 per cent after ferric carboxymaltose, against 4 per cent after iron isomaltoside (now called ferric derisomaltose)
Same meta-analysisStill present at the end of follow-up, up to three months, in up to 45 per cent of those given ferric carboxymaltose
Two randomised trials, 245 adults with iron deficiency anaemia, 2020Hypophosphataemia in 75.0 and 73.7 per cent after ferric carboxymaltose, against 7.9 and 8.1 per cent after iron isomaltoside

This matters in Australia because ferric carboxymaltose made up 93.9 per cent of intravenous iron dispensed to women aged 18 to 44 in 2024.

The meta-analysis identified low baseline ferritin, low transferrin saturation and normal kidney function as risk factors. That profile fits many otherwise healthy young women with iron deficiency.

Low phosphate after an infusion is often a laboratory finding with no symptoms, and the trial authors wrote that further research is needed to determine how clinically important the difference between products is.

An analysis of the PREVENTT trial looked at patients given ferric carboxymaltose or placebo before major abdominal surgery. Hypophosphataemia developed in 26 per cent of the iron group against 4.5 per cent on placebo, and in an exploratory analysis of the iron group, patients who developed moderate or severe hypophosphataemia had a longer median hospital stay, 12 days against 9. That is an association in a surgical population, which leaves open whether the infusion caused the longer stay, and it does not translate directly to a healthy woman in general practice.

Skin staining

If iron leaks out of the vein into the surrounding tissue during an infusion, it can leave a brown stain on the skin. Clinical trials have reported skin discolouration in 0.68 to 1.3 per cent of patients.

It features prominently in the guidance because the stain is permanent in many cases, and the best-supported treatment is repeated laser sessions over one to two years. The Medical Board of Australia has reminded doctors to tell patients about this risk before they consent.

Allergic reactions

Serious reactions are uncommon with the modern products. A pooled analysis of randomised trials counted serious or severe hypersensitivity reactions in 29 of 2,683 patients given ferric carboxymaltose and 5 of 3,474 given ferric derisomaltose. The authors noted that head-to-head trials would be needed to confirm the difference between the two.

Australian Prescriber also advises against giving intravenous iron during an active systemic infection.

Reason 3: the evidence in iron deficiency without anaemia

A systematic review and meta-analysis I led of intravenous iron in adults with iron deficiency but no anaemia pooled 21 randomised controlled trials and 3,514 participants. Intravenous iron improved peak oxygen consumption and reduced fatigue compared with placebo, and made no overall difference to quality of life. Mild adverse events were more common in the iron groups.

The quality of the evidence was rated low or very low for every outcome except fatigue, mostly because the included studies carried a high risk of bias.

The IRONWOMAN randomised trial gave 26 recreationally active women with ferritin below 20 ug/L either 1,000 mg of intravenous iron or a saline placebo. The infusion corrected iron status, with a highly variable response between individuals. Running economy and fatigue scores improved at four weeks. Peak oxygen consumption, lactate threshold, haemoglobin mass, mood and quality of life did not differ. The sample was small and was constrained by COVID-19 recruitment problems, which is a real limitation.

Correcting iron deficiency without anaemia does help some outcomes, but the evidence base is thinner than the enthusiasm around infusions suggests. Australian Prescriber makes the same point, noting limited evidence about the benefits of giving iron to people who do not have anaemia.

Reason 4: no Medicare item for giving the infusion

The medicine is subsidised through the Pharmaceutical Benefits Scheme (PBS). The national dispensing analysis points out that there are no Medicare Benefits Schedule items that specifically cover giving intravenous iron, so the cost of the appointment, the nurse, the cannula and the monitoring is either absorbed by public health services or passed on to the woman when it is given in the community.

The authors suggest this creates inequitable access, and they observed that the share of women receiving intravenous iron who held a concession card fell from 30.9 per cent in 2013 to 17.2 per cent in 2024. A general practitioner (GP) who hesitates may also be thinking about what the infusion will cost you.

Women's ratings of infusions and tablets

In a survey study of 403 exercising women who were, or had been, iron deficient, sentiment towards iron infusions was strongly positive, while sentiment towards oral iron was only moderately positive, and many participants felt tablets had done nothing for them.

That is perception from a survey, and it helps explain the gap between what women ask for and what the guidance recommends. The useful question is whether an infusion is right for you, now.

Nothing here is a recommendation for or against an infusion in your case. The studies describe groups of people, and the decision belongs with your treating clinician.

Indications for intravenous iron

Australian Prescriber lists six main indications for intravenous iron, and surgery and pregnancy have their own consensus guidance; all of them, with the ferritin thresholds for each setting, are set out in what iron level you need for an iron infusion.

Questions for your doctor

  1. Have I had a fair trial of oral iron, about 60 to 90 days taken in a way that gives it a chance?
  2. Do we know the cause, and is iron still being lost faster than it can be replaced?
  3. If an infusion is appropriate, which product, and does the risk of low phosphate differ between the options?
  4. What should I report during the infusion? Pain, swelling, pressure or prickling at the site are the signs that it should be stopped.
  5. What will it cost me to have it given, and where?
  6. When will my iron studies be rechecked? Australian Prescriber suggests roughly 60 to 90 days after intravenous iron.

If you have given oral iron a fair trial and are still depleted and unwell, that is a legitimate reason to raise intravenous iron, and a good clinician will take it seriously.

Related articles

Sources

The figures on this page come from these papers.

This article is educational and not medical advice. Decisions about intravenous iron belong with a qualified clinician who knows your full history.

Iron Risk Check

If you are not yet sure you are iron deficient, start with the iron risk check. It walks through the risk factors and symptoms linked to iron deficiency and tells you whether a ferritin test is worth raising with your general practitioner (GP). It is free, takes about two minutes and does not diagnose anything. If you would rather talk it through with me, book a call.

Take the assessmentBook a discovery call