Let’s get those iron levels up.
Your doctor may prescribe iron tablets or liquid iron, when a blood test shows you need more iron. What do you need to know…
ACKNOWLEDGEMENTS: Information on this page is adapted from - Department for Health and Wellbeing, Government of South Australia. A guide to taking iron tablets. Oct 2023 22
Why might I be prescribed iron tablets or iron liquid?
Why might I be prescribed iron tablets or iron liquid?
Your doctor will prescribe iron tablets or liquid when a blood test shows that you need more iron. Once you are already low in iron it is difficult to get enough iron back into your body just by changing your diet. Iron tablets and liquids contain iron at higher levels than food. They help to replace iron more quickly. High dose iron supplements should only be taken when recommended by your doctor.
Are all iron tablets or iron liquids the same?
Are all iron tablets or iron liquids the same?
No. The amount of iron in different tablets or liquids varies quite a lot. Many different iron tablets and tonics can be bought over-the-counter (without a prescription) but not all of these have enough iron in them to make a difference. It is important that you take the tablet recommended by your doctor.
How do I take iron tablets?
How do I take iron tablets?
- Follow the instructions given by your doctor about how many tablets you should take and when to take them.
- Take the tablets whole, do not crush or chew them.
- Iron is best absorbed on an empty stomach (one hour before or two hours after a meal) with a glass of water or juice. Vitamin C in fruit juice can help a bit more iron get into the body but is not essential – water is fine.
- DO NOT take your iron tablet or liquid with tea, coffee, milk, chocolate, cola or wine as these reduce the amount of iron absorbed by the body.
- DO NOT take the following medicines at the same time as iron tablets or liquid – calcium; antacids (eg. Mylanta and Gaviscon); some medications for osteoporosis, thyroid or Parkinson’s; some antibiotics. Check with your doctor or pharmacist how many hours to space them out by.
How do I know that my iron supplements are working?
How do I know that my iron supplements are working?
After four weeks, talk to your doctor again so they can assess how you are responding to the oral iron supplements19-21. If you are still noticing the symptoms of iron deficiency, including fatigue, paler skin than usual, headaches or shortness of breath, then you should let your doctor know.
What side effects might I get?
What side effects might I get?
Not everybody gets side effects from iron tablets or liquid. If you do, they often improve as your body gets used to them. Side effects include:
- Constipation and diarrhoea. Having more fluid and fibre in your diet can help reduce constipation. If needed, ask your doctor or pharmacist for advice about a gentle laxative.
- Tummy upset, nausea (feeling sick) or tummy pain (cramps). Taking iron with food or at night can help. These symptoms can also be helped by taking iron in smaller amounts (eg. taking 1 tablet two or three times a week) or taking a lower dose of iron each day (eg. using iron liquid) and slowly increasing the amount – these changes should only be made after talking with your doctor.
- It is normal for iron tablets to make your bowel motions (poo) turn black.
Some people are not able to tolerate iron tablets or iron liquid. If this does happen to you, it is important you inform and discuss this with your doctor.
How long will I need to take iron tablets?
How long will I need to take iron tablets?
A course of treatment is usually at least several months. The length depends on the reason for your lack of iron and how you respond to treatment. Your doctor will arrange further blood tests to check that the tablets are working and further plan your treatment. Make sure you ask when this needs to be done. There may also be times that you need to stop your iron tablets briefly (eg. before a colonoscopy or after an operation). If they are stopped, make sure you know when you need to start taking them again.
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