Iron Deficiency
Low iron stores, which can leave you tired, breathless and eventually anaemic. Common with heavy periods, pregnancy and low-iron diets. Easy to fix, but the cause matters as much as the iron.
The iron deficiency ladder
Start at the bottom, climb only if you need to. Tablets work for most people; finding why you’re low is not optional.
- Step 1 · Self-careIron-rich foodRed meat, chicken, fish, eggs, legumes, tofu and iron-fortified cereals.
- Works
- Not tested as a fix in trials; helps keep stores up, but rarely enough alone for a real deficiency
- Cost
- Your usual grocery bill
- How long
- Ongoing
- Watch for
- Tea and coffee with meals block iron absorption.
Spinach is fine, but it isn’t Popeye-level iron. Plant iron is poorly absorbed.
- Step 2 · PharmacyIron tabletsIdeally every second day, on an empty stomach, with tea, coffee, milk, calcium and antacids kept 2 hours away.
- Works
- About 7 in 10 respond within 2 weeks; haemoglobin should rise about 20 g/L by 4 weeks
- Cost
- About $10–20 a month, less on alternate days
- How long
- At least 3 months, then a repeat blood test
- Watch for
- Dark stools (harmless), constipation, nausea. Keep away from children: an overdose can be fatal.
Every second day often beats daily: better absorbed, kinder to your gut.
- Step 3 · PrescriptionTreat the cause: heavy periodsOptions include tranexamic acid, a hormonal IUD or the pill.
- Works
- Tranexamic acid or the pill cut bleeding by about a third to a half; a hormonal IUD by up to about 90%
- Cost
- Tranexamic acid $25 on the PBS ($7.70 concession); hormonal IUD $25 on the PBS plus insertion fees
- How long
- Months to years
- Watch for
- Tranexamic acid isn’t for people with a history of clots.
Topping up a leaking bucket works better once you fix the leak.
- Step 4 · PrescriptionIron infusionA drip of 15 to 30 minutes, for when tablets fail or aren’t tolerated, poor absorption, later pregnancy, or when iron is needed fast.
- Works
- Refills stores in one or two visits; haemoglobin rises over 2–4 weeks, a little faster than with tablets in trials
- Cost
- Iron is $25 on the PBS ($7.70 concession); clinic fees vary, from bulk-billed to a few hundred dollars
- How long
- One or two visits, then a blood test
- Watch for
- Headache, aches or flushing for a day or two. Report stinging or swelling at the drip site at once: leaks can cause permanent brown staining. Can lower phosphate, mainly after repeats.
Faster, not fancier. Tablets still win for most people.
- Step 5 · SpecialistFinding hidden blood loss (gastroscopy and colonoscopy)Looks for bleeding or poor absorption in the gut, including coeliac disease.
- Works
- Finds the cause in many men and people past menopause; bowel or stomach cancer in about 1 in 10 to 12
- Cost
- Free in the public system (expect a wait); private often several hundred dollars after rebates
- How long
- A day procedure
- Watch for
- Essential if you are a man, past menopause, or have bowel symptoms or weight loss.
In men and after menopause, low iron is a clue, not a diagnosis.
Save your money
Popular, heavily marketed or often asked about, but the evidence is weak or says no.
- A vitamin C chaserA 2020 trial found no added benefit to taking it with iron tablets. Save the orange juice for breakfast.
- Iron ‘fish’ and cast-iron pansThe randomised trial of an iron cooking fish found no rise in haemoglobin, and pans add an unpredictable trickle. Fine for cooking, not for refilling empty stores.
- Tonics and multivitaminsMost contain a fraction of the iron in a proper iron tablet: fine as a top-up, far too little to fix a deficiency.
- Pricey ‘gentle’ or slow-release ironSome are kinder on the stomach, but slow-release types can let iron slip past where it’s best absorbed. Try a standard tablet every second day first.
What you can do
- Take tablets every second day, away from tea, coffee and milk.
- Expect dark stools. Black, sticky, tar-like ones are different: see your GP.
- Store iron tablets out of children’s reach.
See your GP if
- Black or bloody stools, or a change in bowel habits
- Weight loss you can’t explain
- No better after a few weeks of treatment
Call 000 for chest pain, severe breathlessness or fainting.
Common questions
Is an iron infusion better than tablets?
Not for everyone. Tablets are the usual first step and work for most people. An infusion is used when tablets don’t work or aren’t tolerated, with poor absorption, in later pregnancy, or when iron is needed quickly.
How long do iron tablets take to work?
Haemoglobin usually rises within 3 to 4 weeks, but refilling stores takes at least 3 months, then a repeat blood test. Taking iron every second day is absorbed better and causes fewer side effects for many people.
When is the best time to take iron tablets?
On an empty stomach. Keep tea, coffee, milk, calcium and antacids at least 2 hours away. Adding vitamin C gave no extra benefit in a 2020 trial.
What are the side effects of an iron infusion?
A headache, aches or flushing for a day or two are common. Rarely, iron leaking from the drip causes permanent brown skin staining, so report stinging or swelling at once. It can also lower phosphate, mainly after repeat infusions.
What are the symptoms of low iron?
Tiredness, breathlessness on exertion, pale skin, headaches, poor concentration, hair shedding, brittle nails and restless legs. Many people have no symptoms until iron is quite low.
What foods are high in iron?
Red meat, chicken, fish and seafood have the best-absorbed iron. Legumes, tofu, leafy greens and iron-fortified cereals also help, especially eaten with vitamin C (such as citrus or capsicum). Tea and coffee with meals reduce absorption.
What ferritin level means low iron?
Ferritin measures iron stores. In Australia, a ferritin below 30 µg/L is now widely used as a sign of iron deficiency in adults, even if haemoglobin is normal. Your GP will interpret it with your symptoms and other results, as inflammation can raise ferritin.
Helpful resources
- Jean Hailes: Heavy periods fact sheetHow to tell if your periods are heavy and what can help. Heavy periods are the most common cause of low iron in women. Free.
- healthdirect: Foods high in ironAnimal and plant sources of iron, plus tips to absorb more from your food. Free.
- Lifeblood: Iron health and blood donationFor regular blood donors: how giving blood affects iron, ferritin testing and protecting your iron stores. Free, Australia.
Evidence and more information
- Healthdirect: Iron deficiency
- Lifeblood: Iron deficiency
- Healthdirect: Iron infusion
- Australian Prescriber: Skin staining from iron infusions
- PBS: Tranexamic acid
- BSG guideline (2021): Iron deficiency anaemia in adults
- Cochrane: Hormonal IUD for heavy periods
maladywise.com/iron/