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HealthInfo Waitaha Canterbury

Taking iron supplements

Te kai āpitihanga rino

Iron deficiency (lack of iron) can make you feel tired, faint and breathless. It can also make you look pale, and it may affect your ability to concentrate.

Low iron is not the only cause of these symptoms. If you think you are low in iron, talk to your general practice team. You will need a blood test to diagnose iron deficiency. If the level of iron in your blood is low, your general practice team may prescribe an iron supplement. You may need to take it for several months.

Once your levels are back to normal, it should be possible to get all the iron you need from eating a wide variety of healthy food without supplements. Taking iron supplements if you are not low in iron may be harmful, especially in tamariki (children).

Types of iron supplements

There are different types of iron supplements available. They come in tablet or liquid form. Some are available in the supermarket and over the counter at the pharmacy. You can also get some on prescription from your general practice team or dietitian. Your general practice team, pharmacist or dietitian can advise which is best for you.

Tips on taking iron supplements

Side effects

Some people have side effects when taking iron. The most common side effect is dark-coloured bowel motions (poos), which are not harmful. Other side effects can include feeling sick (nausea), an upset stomach, constipation or diarrhoea.

You might be able to reduce side effects by:

If you have tried all these things and you still have side effects, ask your general practice team, dietitian or pharmacist for advice. If you stop taking the supplement, your iron levels will not improve.

Liquid iron supplements

Liquid iron supplements can sometimes stain your teeth. To prevent or reduce these stains:

If iron supplements do not work

Occasionally, iron supplements are not enough to get your iron levels up. In this case, you may need to have Intravenous (IV) iron.

Written by HealthInfo clinical advisers. Last reviewed November 2023.


See also:

How to get your daily iron

Iron-rich meal ideas

Page reference: 122363

Review key: HIANA-16978