What is the Erythropoietin Test?

The Erythropoietin (EPO) test measures the level of erythropoietin in the blood, a hormone primarily produced by the kidneys. Erythropoietin stimulates the bone marrow to produce red blood cells in response to low oxygen levels in the body.

EPO plays a central role in maintaining adequate haemoglobin and oxygen delivery to tissues. Abnormal levels may indicate kidney-related anaemia, bone marrow disorders or inappropriate red blood cell production.

This test is commonly used alongside full blood count and iron studies to clarify the cause of anaemia or polycythaemia.

Why do I need an Erythropoietin test?

You may need this test if you have unexplained anaemia or an abnormally high red blood cell count. Measuring erythropoietin helps determine whether the kidneys are producing appropriate signals to stimulate red blood cell production.

The test also supports differentiation between primary bone marrow disorders and secondary causes related to kidney disease, oxygen deprivation or hormone dysregulation.

Symptoms and scenarios where testing is recommended:

• Unexplained anaemia
• Chronic kidney disease
• Fatigue or weakness
• Shortness of breath
• Abnormally high haemoglobin or haematocrit
• Suspected bone marrow disorders
• Investigation of polycythaemia
• Monitoring treatment affecting red cell production

Benefits of the Erythropoietin Test

• Clarifies causes of anaemia
  Distinguishes kidney-related from marrow-related causes.
• Assesses kidney hormone function
  Evaluates erythropoietin production capacity.
• Supports diagnosis of polycythaemia
  Helps differentiate primary and secondary causes.
• Guides appropriate treatment decisions
  Supports use of EPO therapy or alternative interventions.
• Complements full blood count results
  Adds hormonal context to red cell abnormalities.
• Useful in chronic disease monitoring
  Supports ongoing management of kidney or marrow conditions.
• Helps avoid misdiagnosis
  Improves diagnostic accuracy in complex cases.
• Simple and informative blood test
  Requires only a standard venous blood sample.

Step-by-Step: How Testing Works

Choose your preferred testing method

You can attend one of our UK partner clinics or arrange a home or hotel visit with a mobile phlebotomist.

Option 1 – In-Clinic Blood Draw

1. Select your nearest UK clinic and book an appointment.
2. A clinician or phlebotomist collects a venous blood sample.
3. The sample is analysed for erythropoietin levels.
4. Results are delivered securely online.

Option 2 – Home or Hotel Phlebotomy (+£60)

1. Book a UK-wide home or hotel visit at a convenient time.
2. A trained phlebotomist collects your blood sample on-site.
3. The sample is transported to the laboratory.
4. Results are uploaded digitally without the need to travel.

Your Results Explained

Low Levels

Low erythropoietin levels may indicate kidney-related anaemia or primary bone marrow disorders.
This suggests inadequate hormonal stimulation of red blood cell production.
Typical UK reference range: ~4–27 IU/L (ranges may vary by laboratory).

Normal Levels

Normal erythropoietin levels suggest appropriate kidney response to oxygen demand.
Red blood cell abnormalities may be due to other causes such as nutrient deficiency.

High Levels

Elevated erythropoietin levels may occur in response to anaemia, chronic hypoxia or secondary polycythaemia.
Further investigation is often required to identify the underlying cause.