An iron treatment given by drip or injection
Ferric carboxymaltose
An iron treatment given into a vein to treat iron deficiency when iron tablets are unsuitable.
What is Ferric carboxymaltose?
Ferric carboxymaltose is an iron treatment given directly into a vein, used to treat iron deficiency or iron-deficiency anaemia when iron taken by mouth does not work well, is not tolerated or is needed quickly. It tops up the body's iron stores so it can make healthy red blood cells. It is given as a drip or injection in a clinic or hospital, often in one or two visits rather than daily tablets. The main things to watch for are a rare allergic reaction during the infusion and, sometimes, a temporary fall in a blood mineral called phosphate.
Education and reference only. This is a plain-language guide to Ferric carboxymaltose — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Ferric carboxymaltose is a form of iron that is given into a vein rather than taken as a tablet. It is used to treat iron deficiency and iron-deficiency anaemia, which is when the body does not have enough iron to make healthy red blood cells, leading to symptoms such as tiredness, breathlessness and looking pale. It is chosen when iron tablets do not work well enough, cannot be tolerated because of stomach upset, or when iron needs to be replaced quickly. It is given in a clinic or hospital, often as just one or two infusions, under healthcare supervision.
How it works
Iron is needed to make haemoglobin, the part of red blood cells that carries oxygen around the body. In iron deficiency there is not enough iron to make enough healthy red cells, which causes anaemia. Ferric carboxymaltose delivers iron straight into the bloodstream, where it is taken up and stored, then used by the bone marrow to make new red blood cells. Because it goes directly into a vein, it bypasses the gut, so it is useful when tablets are not absorbed well or upset the stomach, and it can replace a large amount of iron in one or two visits.
Company & origin
Originated / developed by: Specialist manufacturer.
An iron preparation used in the UK to treat iron deficiency when iron taken by mouth is unsuitable, given into a vein.
Practical use
How to take Ferric carboxymaltose
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given as a drip or injection into a vein by trained staff in a clinic or hospital, not taken at home.
- Stay for the short period of monitoring after the infusion so any reaction can be spotted and treated.
- Tell the staff straight away if you feel unwell, dizzy, itchy or short of breath during the infusion.
- Mention any previous reaction to iron infusions, and any allergies, before treatment.
- Attend any follow-up blood tests so your iron levels and response can be checked.
Weighing it up
Advantages & disadvantages of Ferric carboxymaltose
Advantages
- An effective way to replace iron quickly, often in just one or two visits.
- Useful when iron tablets are not absorbed well, are not tolerated, or are needed urgently.
- Avoids the stomach upset and constipation that iron tablets commonly cause.
Disadvantages
- Must be given into a vein in a clinic or hospital, with monitoring, rather than at home.
- Carries a rare but serious risk of an allergic reaction during the infusion.
- Can cause a temporary drop in blood phosphate and, if it leaks, a lasting skin stain at the drip site.
Practical use
Good to know
A helpful point is that this treatment is usually given as just one or two visits rather than daily tablets, which can be more convenient and avoids the stomach upset that iron tablets often cause. Because it is given into a vein, you will be watched during and for a short time after the infusion, as a rare but serious allergic reaction can happen; the staff are trained to deal with this. The iron can sometimes leak under the skin at the drip site and cause a lasting brown stain, so the site is checked carefully. A common but usually temporary effect is a drop in a blood mineral called phosphate, which the team may check, especially if you have repeated infusions. Iron levels are rechecked after treatment to see how well it has worked and whether more is needed.
Who should not take it / use with caution
- People who have had a serious allergic reaction to ferric carboxymaltose or other injectable iron should not have it.
- It is not used in people who are not actually iron deficient, or in some types of anaemia not caused by lack of iron.
- It is used with care in pregnancy, particularly the early stages, and under specialist guidance where needed.
Monitoring
- Watching you during and shortly after the infusion for any reaction.
- Rechecking iron levels and blood count after treatment to see how well it has worked.
- Checking blood phosphate where appropriate, particularly with repeated infusions.
Side effects
- Headache, dizziness, nausea or a temporary change in taste around the time of the infusion.
- A temporary drop in blood phosphate, which the team may check, especially with repeated infusions.
- Reactions at the drip site, including, if iron leaks out, a lasting brown skin stain.
- Rarely but seriously, a severe allergic reaction during the infusion, which staff are ready to treat.
Key interactions
- Iron tablets taken by mouth are usually stopped around the time of an infusion, as guided by your team.
- Tell your team about all your medicines, although routine interactions with injectable iron are few.
- Let staff know about any previous reactions to iron given by drip or injection.
Available as: A solution given into a vein as a drip or injection.
Answers
Ferric carboxymaltose: frequently asked questions
What is ferric carboxymaltose used for?
It is used to treat iron deficiency and iron-deficiency anaemia when iron tablets do not work well, are not tolerated, or iron needs to be replaced quickly, by giving iron straight into a vein.
Why is it given into a vein instead of as tablets?
Giving iron into a vein bypasses the gut, so it is useful when tablets are not absorbed well or cause stomach upset, and it can replace a lot of iron in one or two visits.
How many treatments will I need?
Many people need only one or two infusions, but it depends on how low your iron is; your team will work out how much you need and recheck afterwards.
Is it safe?
It is generally safe but is given with monitoring because a rare but serious allergic reaction can happen during the infusion, which staff are trained to treat.
What is the brown mark at the drip site?
If the iron leaks under the skin during the infusion it can leave a lasting brown stain, which is why the site is checked carefully throughout.
Authoritative sources
- BNF
- NICE CKS
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