Show Terms
Iron-deficiency anaemia
Published by Bupa's Health Information Team, December 2011.
This factsheet is for people who have iron deficiency anaemia, or who would like information about it.
Iron deficiency anaemia is a type of anaemia caused by not having enough iron in your body. Anaemia is a condition in which the blood can't carry enough oxygen to meet the needs of your body.
About iron-deficiency anaemia
Symptoms of iron-deficiency anaemia
Complications of iron-deficiency anaemia
Causes of iron-deficiency anaemia
Diagnosis of iron-deficiency anaemia
Treatment of iron-deficiency anaemia
Prevention of iron-deficiency anaemia
About iron-deficiency anaemia
You need iron for many important processes inside your body. It's especially important for making haemoglobin – the protein in your blood that carries oxygen.
Iron is absorbed from your food and drink by your bowel. It's carried in your blood to your bone marrow, where blood cells are produced. Here, the iron is combined with proteins to make haemoglobin. Any iron that doesn't get used up is stored in the bone marrow and other organs, such as your liver.
If you don't have enough iron, your body can't make enough haemoglobin to meet its needs. Your red blood cells then become abnormally small and can't carry enough oxygen to your organs and tissues. This leads to the symptoms of anaemia.
Babies, teenagers and women who have heavy periods are more likely to get iron deficiency anaemia.
Symptoms of iron-deficiency anaemia
Common symptoms of all types of anaemia include:
- feeling tired
- looking pale
- increased breathlessness
- feeling your heart racing or thumping (called palpitations)
If you have iron deficiency anaemia, you may also develop other problems, such as:
- brittle nails
- mouth sores or ulcers
- difficulty swallowing
These symptoms may be caused by problems other than iron deficiency anaemia. If you have any of these symptoms, see a doctor.
Complications of iron-deficiency anaemia
If you have anaemia, your heart has to work harder to get oxygen to your vital organs. If left untreated it can lead to problems with your heart and lungs. In the short term, iron deficiency can affect your ability to work and exercise.
Causes of iron-deficiency anaemia
There are a number of causes of iron deficiency anaemia. Some of the most common are listed below.
Loss of blood
This is the most common cause of iron deficiency anaemia and includes:
- heavy menstrual bleeding (if you're a woman)
- bleeding in your stomach or bowel from an ulcer or cancerous growth
- bleeding caused by medicines, such as aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs)
- an injury or a surgical operation associated with heavy blood loss
- bleeding from a hookworm infection, but this usually only affects people in tropical countries
Poor diet or digestion
If you don't get enough iron in your diet, or if it isn't absorbed properly, you can develop iron deficiency anaemia. This can happen, for example, if you:
- don't eat iron-rich foods, such as meat
- have a bowel disorder, such as coeliac disease or Crohn's disease
- have had stomach surgery (especially if you have had a part of it removed)
Other causes
If your body has a sudden demand for extra iron, you may develop iron deficiency anaemia. This can happen, for example, if you have a growth spurt (which is most common during the teenage years) and your body makes more red blood cells to support your developing bones, muscles and tissues. It can also happen if you're a woman and become pregnant, because your body will need more iron to meet the needs of your developing baby.
Diagnosis of iron-deficiency anaemia
Your doctor will ask about your symptoms and examine you. He or she may also ask about your medical history. If your doctor suspects you have anaemia, you will be asked to have a blood test. Your blood will be sent to a laboratory and tested for the following.
- A full blood count. This is to check the level of haemoglobin in your blood, how many of each of the different types of blood cell you have, the size of your red cells, and the amount of haemoglobin in each red cell.
- A blood film. This involves looking at your blood under a microscope to check the size and shape of your red blood cells and to assess the different white cells that are present.
- Serum iron, iron binding capacity and ferritin. The levels of each of these will be measured.
If the blood tests show that you have low levels of haemoglobin with small, pale, red cells, you may have iron deficiency anaemia. This can be confirmed if you also have low levels of ferritin in your blood.
You may need to have further tests to help identify the cause of your iron deficiency. Your doctor may refer you to a haematologist (a doctor who specialises in identifying and treating conditions of the blood) or a gastroenterologist (a doctor who specialises in identifying and treating conditions that affect the digestive system). If you're a woman, your doctor may refer you to a gynaecologist (a doctor who specialises in women's reproductive health).
Please note that availability and use of specific tests may vary from country to country.
Treatment of iron-deficiency anaemia
Treatment involves replacing iron in your body. If a particular condition is causing the iron deficiency, you may also need to have other treatments.
Self-help
If you don't get enough iron, your doctor will give you advice on how to change your diet, or refer you to a dietitian.
Medicines
Taking iron tablets is the best way to make up for the shortage of iron in your body. Your doctor may recommend you take iron tablets two or three times a day for up to six months.
Iron tablets can cause side-effects, such as feeling sick, heartburn, constipation and diarrhoea. You can reduce your risk of getting these by taking the tablets after meals and drinking enough fluids. Always read the patient information leaflet that comes with your tablets and if you have any questions, ask your doctor or pharmacist for advice.
If you're unable to take iron tablets, or if they don't work, your doctor may suggest you have an iron infusion through a drip into a vein. Iron infusions can cause side-effects, such as headache or joint pains and, occasionally, allergic reactions.
Alternatively, you may be able to have iron injections. However, these aren't used very often as they can be painful and may stain your skin.
Hospital treatment
If you have severe anaemia, you may need to have a blood transfusion. This is when red blood cells are given straight into your bloodstream through a small tube (cannula) put into a vein, usually in your arm.
Availability and use of different treatments may vary from country to country. Ask your doctor for advice on your treatment options.
Prevention of iron-deficiency anaemia
You can reduce your risk of developing iron deficiency anaemia by eating a healthy, balanced diet that contains plenty of iron-rich foods. For most people this will provide enough iron without the need to take supplements.
A healthy diet that includes red meat, green vegetables, dried fruit, chick peas, lentils and fortified foods (those that have particular nutrients added during manufacturing), such as breakfast cereals and bread, should contain all the iron you need.
Tags:
Answers to common questions about this topic. Questions have been suggested by health professionals, website feedback and requests via email.
Will my iron-deficiency anaemia need to be monitored? How often should I go back to see my GP?
I get an upset stomach when I take iron tablets, what should I do?
I've heard that taking too many iron tablets can be harmful, why is this?
What is hookworm infection and how does it cause iron-deficiency anaemia?
Will my iron-deficiency anaemia need to be monitored? How often should I go back to see my GP?
Once you have been diagnosed with iron-deficiency anaemia and started treatment, you will need to go back to your GP for further blood tests to make sure that your blood count and iron levels have returned to normal.
Explanation
The most common treatment for iron-deficiency anaemia is a course of iron tablets, such as ferrous sulphate tablets. You should take the tablets as directed by your GP – usually, you will need to take them two to three times a day. Always read the patient information leaflet that comes with your medicine, and if you have any questions ask your GP for advice.
You will be asked to return to your GP two to four weeks after starting your iron tablets for a blood test, to check that they are working. You will then need to return two to four months later to make sure that your haemoglobin level has returned to normal.
Once your GP is happy that your blood count is normal, you will usually need to continue taking your tablets for a further three months. This is to make sure that your body’s iron stores are completely topped up. Once you have stopped taking your tablets, you will need to return to your GP for a blood test after a few months. If your blood count and iron level have fallen again, you will be given another course of iron tablets.
If the iron tablets prescribed by your GP aren’t working, you may be referred to a haematologist for further investigation. A haematologist is a doctor who specialises in treating blood disorders. It's very important to understand why you have iron-deficiency anaemia because it's usually caused by blood loss. In women, this is most often through heavy periods, but in men and older women it’s possible that there is bleeding from your stomach or bowel, so this must be investigated.
If you have any questions or concerns about iron tablets or iron-deficiency anaemia, talk to your GP.
Sources
- Anaemia - iron deficiency. Clinical Knowledge Summaries. www.cks.nhs.uk, accessed 22 September 2009
- Ferrous sulphate. British National Formulary. www.bnf.org, accessed 23 September 2009
I get an upset stomach when I take iron tablets, what should I do?
Some people find that they get an upset stomach when taking iron tablets, but it's important to continue taking the tablets as directed by your doctor if at all possible. If you need to, you can take over-the-counter medicines to ease your stomach symptoms until they settle by themselves.
Explanation
When taking iron supplements, some people find that their digestive system is disturbed. This can cause:
- stomach pain
- constipation or diarrhoea, often with black faeces
- heartburn
- nausea
Usually these symptoms settle down quickly, so there is no need to stop taking your tablets. In the meantime, there are medicines you can buy from your pharmacy to relieve your symptoms, for example, antacids for heartburn or medicines for constipation.
You could also try taking your tablets with or after food rather than on an empty stomach, and as one daily dose instead of spreading them out through the day.
It's important to follow your GP's advice and keep taking your iron tablets as directed. If they are causing you a lot of discomfort and your symptoms don't settle, go back to see your GP before you stop taking them. He or she will be able to advise you on alternative brands or formulations to try.
Sources
- Anaemia - iron deficiency. Clinical Knowledge Summaries. www.cks.nhs.uk, accessed 22 September 2009
- Gaviscon. British National Formulary. www.bnf.org, accessed 23 September 2009
- Ispaghula husk. British National Formulary. www.bnf.org, accessed 23 September 2009
I've heard that taking too many iron tablets can be harmful, why is this?
Taking a large number of iron tablets at one time is extremely dangerous, and can be fatal. It can damage your gut and liver and cause heart failure. Taking iron tablets over a long period of time when you don't need to can also be harmful.
Explanation
Taking too many iron tablets is harmful to your body for two reasons. First, it can damage your gut, and secondly, it can harm organs such as your heart and liver and may cause irreversible damage.
If you have taken too many iron tablets, you must go to hospital as quickly as possible – an iron overdose is a medical emergency. Treatment is best started within one hour of taking the tablets, so it’s important to take immediate action.
Iron overdose is the most common type of childhood poisoning, usually happening when children take tablets meant for adults. Iron tablets are often brightly coloured and sugar-coated, so can be mistaken as sweets by children. It's extremely important to make sure that all medicines and tablets are kept out of the reach of children.
If you take a normal dose of iron tablets over a long period of time when you don't need them, this can also be harmful. Iron can build up in various organs, such as your liver, pancreas and heart, and eventually cause damage. It's particularly important to avoid taking unnecessary iron tablets if you have certain inherited conditions such as genetic haemochromatosis or thalassaemia.
Always read the patient information leaflet that comes with your medicine and follow the recommended dose, unless you have been instructed otherwise by your doctor.
If you have any questions or concerns about iron overdose, talk to your GP.
Sources
- Anaemia - iron deficiency. Clinical Knowledge Summaries. www.cks.nhs.uk, accessed 22 September 2009
- Toxicity, iron. Emedicine. www.emedicine.medscape.com, accessed 23 September 2009
- Iron poisoning - clinical features. GP Notebook. www.gpnotebook.co.uk, accessed 23 September 2009
- Iron salts. British National Formulary. www.bnf.org, accessed 23 September 2009
- Draft Iron and Health report 'Scientific Consultation' June 2009. The Scientific Advisory Committee on Nutrition, 2009. www.sacn.gov.uk
What is hookworm infection and how does it cause iron-deficiency anaemia?
Hookworm infection occurs when a parasitic worm (hookworm) gets into your gut and feeds from the wall of your bowel. This may result in blood loss and is a common cause of iron deficiency in certain parts of the world, such as the tropics.
Explanation
Hookworms are parasitic worms that you can pick up from eating contaminated foods or through your skin, usually the soles of your feet. They are commonly found in developing, tropical countries. It's estimated that over 740 million people in the world have a hookworm infection, but it’s rare in the UK.
Once inside your body, the hookworms pass into your lungs. They are then coughed up and swallowed down into your gut (gastrointestinal tract). Once there, they attach themselves to the wall of your bowel and feed on your blood.
Most hookworm infections are mild and there are usually no symptoms. However, if the infection is more severe, the blood lost from your gut (sucked by the worms) can lead to iron-deficiency anaemia. Other symptoms can include an allergic reaction in a specific part or all over your body, and stomach pain. These symptoms can be caused by many conditions, not just hookworm. It's important that you see your GP to get the correct diagnosis.
Once your GP has examined you and asked about your symptoms, he or she will ask you for a sample of faeces. This is because, once in your bowel, hookworms pass their eggs out through your faeces. You will also be asked to have a blood test. These will both be sent to a laboratory for testing. Once diagnosed, your GP may refer you to a doctor who specialises in treatment of tropical diseases.
Treatment of a hookworm infection is with a medicine called mebendazole. You will need to take it twice daily for three days. You will also need treatment for your iron-deficiency anaemia. This is usually a course of iron tablets, such as ferrous sulphate tablets. Always ask your doctor for advice and read the patient information leaflet that comes with your medicine.
If you have any questions or concerns about hookworm infection or iron-deficiency anaemia, talk to your GP.
Sources
- Anaemia - iron deficiency. Clinical Knowledge Summaries. www.cks.nhs.uk, accessed 22 September 2009
- Aetiology. GP Notebook. www.gpnotebook.co.uk, accessed 23 September 2009
- Hookworm. GP Notebook. www.gpnotebook.co.uk, accessed 23 September 2009
- Hookworm disease. World Health Organization. www.who.int, accessed 23 September 2009
- Hookworm: differential diagnoses & workup. Emedicine. www.emedicine.medscape.com, accessed 23 September 2009
- Hookworm - treatment. GP Notebook. www.gpnotebook.co.uk, accessed 23 September 2009
- Drugs for hookworms. British National Formulary. www.bnf.org, accessed 23 September 2009
Related topics
Anaemia – an overview
Constipation
Indigestion
Laxatives
Treatments for indigestion
Type 1 diabetes
Type 2 diabetes
This information was published by Bupa’s health information team and is based on reputable sources of medical evidence. It has been peer reviewed by Bupa doctors. The content is intended for general information only and does not replace the need for personal advice from a qualified health professional.
Publication date: February 2010.
Iron-deficiency anaemia factsheet
Visit the iron-deficiency anaemia health factsheet for more information.
Further information
-
Food Standards Agency
www.eatwell.gov.uk
-
British Nutrition Foundation
020 7404 6504
www.nutrition.org.uk
Related topics
Anaemia – an overview
Coeliac disease
Folate-deficiency anaemia
Gastroscopy
Healthy eating
Non-steroidal anti-inflammatory drugs (NSAIDs)
Tinnitus
Vitamin B12-deficiency anaemia
Sources
- Anaemia – iron deficiency. Prodigy. www.prodigy.clarity.co.uk, published July 2011
- Anaemia. Lab Tests Online UK. www.labtestsonline.org.uk, published January 2010
- Goddard AF, James MW, McIntyre AS, et al. Guidelines for the management of iron deficiency anaemia. Gut 2011; 60:1309–16. doi:10.1136/gut.2010.228874
- The ferritin test. Lab Tests Online UK. www.labtestsonline.org.uk, published May 2004
- Iron overdose. The Merck Manuals. www.merckmanuals.com, published January 2009
- Haemoglobin and iron. The National Blood Service. www.blood.co.uk, published July 2008
- Hookworm disease. National Institute of Allergy and Infectious Diseases. www.niaid.nih.gov, published September 2010
- Joint Formulary Committee. British National Formulary. 62nd ed. London: British Medical Association and Royal Pharmaceutical Society of Great Britain; 2011
- Hotez PJ, Brooker S, Bethony JM, et al. Hookworm infection. NEJM 2004; 351:799–807. www.nejm.org
- Personal communication, Dr John Houghton, Consultant Haematologist, Spire Manchester Hospital, 21 November 2011
This information was published by Bupa’s health information team and is based on reputable sources of medical evidence. It has been peer reviewed by Bupa doctors. The content is intended for general information only and does not replace the need for personal advice from a qualified health professional.
Related articles
This factsheet is for people who have Crohn's disease, or who would like information about it.
Crohn's disease is an inflammatory bowel disease and can have both short-...
Constipation is a very common condition that affects your usual pattern of bowel movements. Your bowel movements may occur less often than usual, or may be difficult to pass and...