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HealthInfo Canterbury

Taking iron supplements

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, so if you think you are low in iron talk to your doctor or practice nurse, as iron deficiency is diagnosed through a blood test. If the level of iron in your blood is low you may be prescribed an iron supplement, which you may need to take for several months.

Once your levels are back to normal, it should be possible to get all the iron you need from a healthy balanced diet without needing supplements. Taking iron supplements if you are not low in iron may be harmful, especially in men, or women who are not menstruating.

Types of iron supplements

There are different types of iron supplements available and they come in tablet or liquid form. Some are available in the supermarket and over the counter at the pharmacy and others you can only get on prescription from your doctor or dietitian. Your doctor, pharmacist or dietitian can advise what is most appropriate 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 aren't 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've tried all these things and you still have side effects, ask your doctor 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 don't work

Occasionally, iron supplements aren't 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 May 2020.


See also:

How to get your daily iron

Iron-rich meal ideas

Page reference: 122363

Review key: HIIRO-122590