Intravenous (IV) iron therapy

What is IV iron therapy? 

Iron is an essential nutrient for your body. It is an important part of haemoglobin, the red pigment which gives blood its colour and which carries oxygen around your body. You need iron so your body can make new haemoglobin and red blood cells to carry the oxygen your body requires. 

If your blood results have shown that the amount of iron in your blood is low, you may be prescribed iron therapy. IV iron therapy, or iron infusion, is when iron is given directly into a vein to increase the body’s iron levels quickly. It is a more immediate treatment compared to others such as iron tablets or dietary changes. Others forms of iron therapy can include tablets or liquids that can be taken orally. 

Your doctor will discuss which is the best option for you and look at the underlying cause for the iron deficiency and how to correct this. 

Before you receive iron infusions 

Please stop taking your iron tablets the day before coming to your first appointment. 

Please tell your doctor if you have ever had: 

• Severe asthma 
• Eczema or another atopic allergy 
• Systemic lupus 
• Erythematosus 
• Rheumatoid arthritis 
• Any other immune or inflammatory condition. 

Who can have IV iron therapy? 

You should not receive iron infusions if: 

You have liver disease, as certain iron products may not be suitable for you. Please discuss with your hepatologist. 

You are known to be sensitive (allergic) to any iron preparations meant to be given into a muscle or into the vein. 

You have any acute or chronic infections. 

During your iron infusions 

The IV iron is given directly into the vein via a cannula (a tube that is inserted into your vein). The iron infusion is given through a pump and takes between 15 minutes and four hours to complete the transfusion, depending on the iron product you receive. 

Your doctor will confirm which iron preparation you will receive and how long this will take. If you have any pain or discomfort at the place where the infusion is given, please let your nurse/midwife know immediately. 

How often will I need to have an infusion? 

This varies from patient to patient and depends on why you are prescribed the iron therapy. Some patients will only need to have an infusion twice, with the second infusion taking place a week after the first. 

You may need to continue having iron infusions until your blood test levels come into target range or as recommended by your doctor. 

After your iron infusion 

A member of staff will be in the room observing you for 30 minutes after the infusion to ensure you have not had any allergic-like reactions to the iron injection. If you feel well after this, you will be allowed to go home. 

You will then be seen in an outpatient clinic about one month after your infusions. Before your clinic appointment, you will need to have a blood test. This allows the doctor to review the results before your visit to see if you require more iron therapy. If your blood test results are within range, you will not need any further iron infusions. 

IV iron therapy benefits 

Receiving iron infusions can: 

• increase your blood-iron levels 
• increase your haemoglobin levels 
• help you feel less tired 
• give you more energy 
• improve your concentration 
• reduce breathlessness when exercising 
• no gastrointestinal side effects such as constipation which can occur with iron tablets. 

IV iron therapy risks and side effects 

IV iron therapy is widely used and considered safe in pregnancy but, like all medications, can have some unwanted side effects that include: 

Common side effects 

• A metallic taste in your mouth which normally disappears within 15 minutes of you having the injections. 
• Feeling lightheaded, sick, or dizzy 
• Reactions where your infusion is given (such as redness, swelling, burning, pain, bruising, discoloration and/or irritation) 
• Lowering of the blood pressure 
• Tingling or numbness of the limbs 
• Abdominal discomfort 
• Skin flushing 
• Swelling of hands and feet. 

You may also experience delayed reactions, which can be severe. This is characterised by joint pain, muscle pain and sometimes fever. The onset varies from several hours up to four days after you receive your iron infusion. Symptoms usually last two to four days and settle spontaneously (almost without noticing) or with the use of simple pain relief such as paracetamol. 

Uncommon side effects 

Iron infusions can sometimes lower phosphate levels. A blood test may be needed to check the phosphate level; sometimes oral phosphate tablets are needed to replace the phosphate. This situation is uncommon. 

Rare side effects 

On rare occasions, skin staining can occur which can be significant and permanent. If you experience any discomfort during the infusion, it is important that you tell the nurse/midwife immediately. Should you feel unwell in the days or weeks after the infusion, you should contact your doctor or your nurse/midwife. 

Allergic reactions with iron infusions are considered rare (between 1 in 1,000 and 1 in 10,000 patients). 

Alternatives to IV iron therapy 

An alternative iron therapy option to iron infusions is taking iron supplement tablets. If you are prescribed iron tablets, you may have to take these for a considerable length of time to maintain the haemoglobin levels in your blood. 

Iron supplement tablets should be taken on an empty stomach (preferably one hour before food), with a drink containing vitamin C (e.g. orange juice). 

Please speak to your doctor if you have any questions about alternative iron therapy treatments.