Iron deficiency anaemia
Iron is part of haemoglobin, the protein your red cells use to carry oxygen. Once the body's iron stores run out, the bone marrow keeps turning out red…
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Medicines commonly prescribed for Iron deficiency anaemia
For informational purposes only. Always consult a doctor before using any medicine.
Dosage form: MODIFIED-RELEASE TABLET, 80 mgActive substance: ferrous sulfateManufacturer: Pierre Fabre Iberica S.A.Prescription requiredDosage form: MODIFIED-RELEASE TABLET, 105 mgActive substance: ferrous sulfateManufacturer: Teofarma S.R.L.Prescription required
Iron is part of haemoglobin, the protein your red cells use to carry oxygen. Once the body's iron stores run out, the bone marrow keeps turning out red cells, but small pale ones, and each carries less oxygen than it should. This is the commonest anaemia in the world, and putting the iron back is not particularly difficult. The difficulty lies elsewhere: iron deficiency anaemia is almost never a disease in its own right. It is the trace of blood being lost somewhere, or of iron not being absorbed. That is why the question here is less "what do I take" than "where is it going".
How it feels
The shortfall builds up over months, the body has time to adjust, and people put their state down to age, work or short nights. The early complaints point to nothing in particular:
- tiredness that a weekend does not fix, and less stamina than before;
- breathlessness on the stairs and with efforts you never used to notice;
- noticeable palpitations;
- pallor, easier to see on the inside of the lower eyelid, the lips and the nail beds than on the face;
- headache, dizziness, ringing in the ears;
- feeling cold all the time, with cold hands and feet.
These other signs, by contrast, point fairly precisely at iron, because they are rare in other anaemias:
- odd cravings: an urge to chew ice, to eat chalk, clay, starch, paper or raw dough, to sniff petrol or fresh paint. People rarely mention it to a doctor, taking it for a personal quirk, and yet there is no more recognisable sign than this;
- restless legs: an unpleasant fidgetiness in the legs in the evening and in bed that forces you to move them;
- a smooth, polished-looking, sore tongue and cracks at the corners of the mouth;
- brittle nails, sometimes dipped into a spoon shape;
- noticeably more hair coming out;
- difficulty swallowing dry food, an uncommon but long-recognised companion;
- in children, listlessness, poor appetite, slow weight gain, poor concentration at school.
When it cannot wait
Call an ambulance (in Spain, Italy, Portugal, Poland and Ukraine that is the single European number 112) if there is:
- vomiting of blood or of something like coffee grounds;
- black, tarry, sticky stools, or heavy bleeding from the back passage;
- chest pain or severe breathlessness at rest;
- fainting or confusion;
- bleeding you cannot stop, including from the womb.
See a doctor the same day or within a few days — no ambulance, but no putting it off either:
- anaemia found in a man or in a woman past the menopause. With no obvious blood loss, this is a direct reason to look for a source in the stomach and bowel: sometimes a tumour sits behind such an anaemia, and it is found while it is still curable;
- blood in the stool, a lasting change in bowel habit, weight loss with no explanation;
- anaemia in pregnancy;
- haemoglobin falling again after a course of treatment has already been completed.
Where the iron goes
Blood loss. In women of childbearing age, heavy, long periods come first, and behind them may sit fibroids, endometriosis, polyps or a coil. In the gut the bleeding is usually invisible, a drop at a time: stomach and duodenal ulcers, erosive gastritis and oesophagitis, haemorrhoids and anal fissures, diverticula, polyps, vascular malformations of the bowel. Taking anti-inflammatory painkillers regularly raises the risk of such bleeding, and on blood-thinning medicines things start to bleed that had been silent until then. Stomach and bowel cancer stand apart on this list: an uncommon cause, but precisely the reason that anaemia in a man or in a post-menopausal woman is not treated as settled until the bowel has been looked at.
Higher demand. Pregnancy, particularly the second half and twin pregnancies; breastfeeding; the growth spurts of childhood and adolescence; regular blood donation; heavy endurance training.
Poor absorption. Coeliac disease is a common cause and easily missed — sometimes anaemia is its only sign. Then come atrophic gastritis and Helicobacter pylori infection, inflammatory bowel disease, stomach surgery including weight-loss operations, and long-term use of medicines that cut stomach acid, since without acid the iron in food is absorbed less well.
Diet. A plant-based diet with no thought given to iron sources, monotonous eating in older people, restrictive diets. In babies, large amounts of cow's milk introduced early in place of breast milk or formula.
Parasites. Intestinal worms, hookworm above all, are the commonest cause of iron deficiency worldwide. Worth remembering after a long stay in the tropics or subtropics.
Which tests answer the question
The starting point is a full blood count. With iron deficiency the haemoglobin is low and the red cells are small and pale — on the report that shows up as the mean cell volume and the mean cell haemoglobin.
The decisive figure is the ferritin, which reflects the body's iron store. A low ferritin means iron deficiency and nothing else. There is a catch, though: ferritin rises with any inflammation, infection, liver disease or tumour, so a normal value in an unwell person does not rule the deficiency out. In that situation the transferrin saturation and the inflammatory markers are looked at as well. Vitamin B12 and folate are usually checked at the same time, since a lack of either causes similar complaints and often runs alongside.
There is also an inherited condition that mimics iron deficiency: in thalassaemia the red cells are small too, but the iron store is normal or high, and giving iron there is not merely useless but harmful. The same ferritin tells them apart — which is why you should not put yourself on iron on the strength of a low haemoglobin read off somebody else's report.
The second half of the work-up is finding the source. Depending on age, sex and symptoms, that means a faecal test for hidden blood, gastroscopy and colonoscopy, a blood test for coeliac disease and, in women, an assessment of menstrual blood loss and a gynaecological examination with an ultrasound scan.
Putting the store back
Treatment rests on iron taken by mouth. The doctor chooses the salt and the dose; multivitamins containing iron are no use for treating anaemia, as the amount in them is far too small.
- Take it on an empty stomach or between meals, with water or a drink supplying vitamin C. Tea, coffee, cocoa, milk, calcium supplements and antacids bind iron at that moment — keep them a couple of hours away from the tablet.
- Daily dosing is not always best: after a dose the body shuts down iron absorption for about a day, so for some people alternate-day dosing works just as well and is easier on the stomach. This is one to discuss with your doctor rather than decide alone.
- Side effects are routine: nausea, tummy pain, constipation or loose stools, a metallic taste. Stools go dark in almost everybody — that is the colouring of the medicine, not blood, and it is nothing to be alarmed by. If it is going down badly, taking it with food helps, as does lowering the dose, switching to a different iron salt or moving to alternate days. Abandoning the course because of side effects is the worst option of all.
- Haemoglobin begins to climb after two or three weeks and comes back to normal in about two months. That is not the end of it: treatment continues for several months more to refill the emptied store, otherwise the whole thing repeats itself within half a year. Your doctor sets the follow-up tests.
Iron into a vein is used when tablets do not work or do not fit: intolerance, inflammatory bowel disease, previous stomach surgery, chronic kidney disease, continuing blood loss, and severe anaemia late in pregnancy when there are no longer months to spare. The infusion is given in a clinical setting under supervision. Transfusion is a measure for severe anaemia with threatening symptoms, not a way of restocking iron.
Keep iron preparations where a child cannot reach them. A few adult-strength tablets can be fatal to a small child, and the first hours after such a poisoning often pass in deceptive calm. If your child may have swallowed some, call an ambulance straight away without waiting for symptoms.
What food actually does
Iron from meat, liver, poultry and fish is absorbed many times better than iron from plants. Plant sources are worth having too — pulses, tofu, buckwheat and oats, pumpkin seeds and sesame, nuts, dried fruit, iron-fortified cereals and bread — but they yield less. Dark leafy greens deserve a separate mention: there is plenty of iron in them, but it is tightly bound and poorly absorbed, so counting on spinach is an old misconception.
Vitamin C in the same meal helps: peppers, citrus, berries, sauerkraut.
And an honest caveat: food covers the daily requirement and holds on to what has been gained, but an anaemia that has already set in will not be cured by eating — that would take years. Diet comes after the tablets, not instead of them.
What happens if it is left alone
The heart has to move more blood to deliver the same oxygen: the pulse stays fast, in older people and in those with heart disease angina episodes become more frequent and heart failure slips out of control. Infections are harder to shake off. In pregnancy, untreated anaemia raises the risk of premature birth, of low birth weight and of heavy bleeding during delivery. In young children attention, memory and the pace of development suffer, and it is not fully made up afterwards.
But the greater danger lies not in the anaemia itself but in the cause nobody looked for. While a low haemoglobin is dutifully lifted with tablets, the source that was never found carries on bleeding.
Online consultation
In an online appointment the doctor will go through your symptoms and your results and tell you the main thing: what is missing from the work-up. They will gauge how heavy your periods are, go through the medicines you take regularly, ask about your bowels and your weight, and work out whether a ferritin is needed and whether you should be referred for a gastroscopy or a colonoscopy. If treatment has already begun, the appointment is the place to sort out side effects, adjust how and when you take the tablets, and learn when to repeat the blood test and how much longer to keep going so the anaemia does not return. Blood cannot be drawn and the bowel cannot be examined online, but you can avoid spending half a year treating the symptom instead of the cause.
This material is for information only and does not replace medical advice.
Consult with a doctor about Iron deficiency anaemia
Discuss your symptoms and possible next steps with a doctor online.
Online doctors for Iron deficiency anaemia
Discuss your symptoms and possible next steps for Iron deficiency anaemia with a doctor online.
