Anemia
Also known as Anaemia, Low haemoglobin
This article is general health information for the selected condition. It is not a diagnosis and does not replace clinical judgement. If you have questions or need treatment advice, please consult a qualified healthcare professional.
What is anemia?
Anemia means the blood carries less oxygen than the body needs, either because there are too few red cells or because each cell holds too little haemoglobin. It is a finding rather than a final diagnosis, so the important clinical step is establishing the cause. Iron deficiency is the most common reason worldwide.
Causes
- Iron, vitamin B12 or folate deficiency
- Blood loss from menstruation or the gastrointestinal tract
- Chronic kidney disease reducing erythropoietin
- Chronic inflammatory or malignant disease
- Inherited disorders such as sickle cell disease or thalassaemia
- Increased red cell destruction, known as haemolysis
Symptoms
- Fatigue and reduced exercise tolerance
- Pale skin, lips or inner eyelids
- Shortness of breath on exertion
- Dizziness or light headedness
- Palpitations
- Headache and poor concentration
- Cold hands and feet
Risk factors
- Heavy menstrual bleeding
- Pregnancy
- Diet low in iron or vitamin B12
- Gastrointestinal disease affecting absorption
- Chronic kidney disease
Diagnosis
- Full blood count with red cell indices
- Ferritin and iron studies
- Vitamin B12 and folate levels
- Reticulocyte count to assess marrow response
- Endoscopy or colonoscopy when occult blood loss is suspected
Treatment
- Treating the underlying cause, which is the priority
- Oral iron replacement, often for three to six months
- Intravenous iron when oral iron is not tolerated or absorbed
- Vitamin B12 injections or folate supplements
- Blood transfusion for severe or symptomatic anemia
Self care
- Take iron or vitamin supplements exactly as prescribed
- Take iron with vitamin C and away from tea, coffee, dairy and antacids
- Expect black stools on iron, which is harmless
- Include iron rich foods such as red meat, pulses and leafy greens
- Pace activity while your haemoglobin recovers
- Do not self prescribe long term iron without knowing the cause
When to see a doctor
Book an appointment if:
- Persistent tiredness, breathlessness or pallor
- Heavy periods affecting your daily life
- Anemia returning after previously being corrected
- Blood in the stool or black stools not explained by iron
- Poor tolerance of iron tablets
- Anemia found on a blood test without an obvious cause
Some symptoms need emergency care rather than an appointment. See the warning signs listed above.
Prevention
- Eat a diet with adequate iron, B12 and folate
- Treat heavy menstrual bleeding rather than tolerating it
- Take supplements in pregnancy as advised
- Manage coeliac or inflammatory bowel disease well
- Attend bowel screening when invited
- Space blood donations appropriately
Outlook
Outlook depends entirely on the cause. Nutritional deficiency corrects fully with replacement, though treatment usually continues for months to rebuild stores. Anemia from chronic kidney disease or ongoing inflammation improves when the underlying condition is managed. The important part is identifying why it happened, since unexplained iron deficiency can be the first sign of a treatable bowel problem.
Common questions
Why does the cause of anemia matter so much?
Anemia is a signal, not a diagnosis. Iron deficiency in an adult can be the first sign of gastrointestinal bleeding, so treating the low haemoglobin without finding the source can delay an important diagnosis.
How long does it take to correct iron deficiency?
Haemoglobin usually begins to rise within two to four weeks of starting iron, but treatment normally continues for several months afterwards to rebuild body iron stores.
Can diet alone fix anemia?
Diet helps prevent deficiency but is rarely enough to correct established anemia. Supplements or treatment of the underlying cause are usually required.
References
Important: Dard AI is not a medical device and does not diagnose, treat, or replace clinician judgement. This article is general information only. Always consult a qualified healthcare professional about diagnosis and treatment, and seek emergency care for severe or rapidly worsening symptoms.