What it measures
- Haemoglobin
- Haematocrit
- Red blood cell count
- White blood cell count
- Platelets
- MCV
- MCH
- MCHC
Who it’s for
- Feeling tired, weak or short of breath
- Looking pale or feeling dizzy
- Picking up one infection after another
- Bruising easily or having heavy periods
- A routine check before travel, surgery or a new fitness plan
What a full blood count tells you
Your blood contains three kinds of cell, and an FBC counts each one. Red cells and haemoglobin carry oxygen; when they’re low you have anaemia, one of the most common physical reasons for tiredness. White cells fight infection, so a high count can point to infection or inflammation and a low count can leave you more prone to illness. Platelets help your blood to clot.
Small cells or large cells?
If you’re anaemic, the size of your red cells (MCV) is an important clue. Small, pale cells usually point to low iron, often from heavy periods, diet or blood loss. Large cells are more often linked to low vitamin B12 or folate, heavy drinking or an underactive thyroid. Your GP can use your FBC to decide what to check next.
How to prepare
- Drink a couple of glasses of water beforehand: it makes the sample quicker and easier to take.
- No fasting needed. Eat and drink as normal.
How it works at our Croydon clinic
Book online
Choose your test and a time that suits you. No GP referral needed.
A 15-minute visit
A trained clinician takes a small blood sample at 169 Shirley Road, Croydon. Tell us if you’re nervous.
Results in 1–3 days
A clear report showing each result against its reference range.
Next steps
Share your report with your GP, who can arrange NHS follow-up if anything needs it.
Questions
Do I need to fast for a full blood count?
No. Eat and drink normally. Being well hydrated makes the sample easier to take.
Can a full blood count detect cancer?
Not on its own. An FBC can show changes that need looking into, such as unexplained anaemia or an unusual white cell count, but it can’t diagnose or rule out cancer. If anything is unusual we’ll recommend you see your GP.
How much blood is taken?
Just one small tube of a few millilitres. The sample itself takes a minute or two.
How much is a Full Blood Count in Croydon?
£70 at our clinic at 169 Shirley Road, Croydon, including taking your blood sample and your report.
How quickly will I get my results?
Usually within 1 to 3 days, in a clear report showing each result against its reference range.