Iron supplements

  • Iron supplements are best absorbed when thay are taken an hour before meals. However, to reduce stomach upset, you may prefer to take your doses after meals.
  • Stomach upset, constipation and diarrhoea are side-effects that can occur with iron supplements.
  • Keep iron supplements out of the reach and sight of children - iron is a common cause of accidental overdose in children.
Type of medicine Oral iron
Used for Prevention and treatment of iron-deficiency anaemia
Also called Ferrous sulphate, ferrous fumarate, ferrous gluconate, sodium feredetate, polysaccharide-iron complex
Ironorm®; Feospan®; Ferrograd®; Fersaday®; Galfer®; Niferex®; Sytron®
Available as Tablets, capsules and oral liquid
Modified-release tablets and capsules

Anaemia caused by a lack of iron is called iron-deficiency anaemia. Iron is needed to make haemoglobin which carries oxygen around in the bloodstream and is what makes red blood cells red.

If someone has iron-deficiency anaemia, it means that there is not enough oxygen being carried around the body. This can cause tiredness, breathlessness, palpitations, dizziness and headache.

Iron is found naturally in certain foods, but in some conditions where people do not get enough iron from their normal diet, an iron supplement may be useful.

Before taking iron supplements make sure your doctor or pharmacist knows:

  • If you are pregnant, trying for a baby or breast-feeding.
  • If you have bowel irritation or inflammation.
  • If you are taking any other medicines, including those available to buy without a prescription, herbal and complementary medicines.
  • If you have ever had an allergic reaction to this or to any other medicine.
  • Before starting this treatment, read the manufacturer's printed information leaflet from inside the pack.
  • Iron supplements are absorbed better if they are taken an hour before meals. However, you may prefer to take your iron supplements with or just after your meals to reduce the risk of stomach irritation.
  • Try to take your doses at the same times each day to avoid missing any.
  • If you do forget to take a dose don't worry, just leave out the missed dose and take the next when it is due. Do not take two doses together to make up for a forgotten dose.
  • If you suspect that you have taken, or someone else (and especially if it is a child) has taken, an overdose of iron, go to the accident and emergency department of your local hospital at once. Take the container with you, even if it is empty.
  • Do not take iron supplements for longer than a few months without medical advice from your doctor, nurse or pharmacist.
  • If you buy any medicines, check with your pharmacist that they are safe to take with iron supplements. Some antacids may interfere with the way iron is absorbed.
  • Iron supplements may darken your stools. This is completely harmless and is no cause for concern.

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

Common side-effects - these affect less than 1 in 10 people who take this medicine What can I do if I experience this?
Feeling sick, stomach pain Eat little and often. Stick to simple or bland foods
Constipation Try to eat a well-balanced diet containing plenty of fibre and drink 6-8 glasses of water each day
Diarrhoea Drink plenty of water to replace lost fluids

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

  • Keep all medicines out of the reach and sight of children.
  • Store in a cool, dry place, away from direct heat and light.
  • If you are having an operation or any dental treatment, tell the person carrying out the treatment which medicines you are taking.
  • This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.
  • Never keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.
  • If you have any questions about this medicine ask your pharmacist.

Further reading & references

  • British National Formulary; 62nd Edition (Sep 2011) British Medical Association and Royal Pharmaceutical Society of Great Britain, London

Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.

Original Author:
Helen Allen
Current Version:
Peer Reviewer:
Prof Cathy Jackson
Last Checked:
Document ID:
3406 (v24)
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