In short: A phlebotomist is a healthcare worker trained to take blood samples, usually from a vein in the arm, so they can be tested in a laboratory. You might see one for routine blood tests, health checks, monitoring a medicine or condition, or investigating symptoms. Having blood taken normally takes only a few minutes.

This guide, written by a Ready Health prescribing pharmacist, explains what phlebotomists do, why you might need a blood test and how to prepare.

What is a phlebotomist?

Phlebotomy is the medical term for drawing blood. A phlebotomist is trained in venepuncture (inserting a fine needle into a vein), using the correct collection tubes, labelling samples accurately and handling them so that results are reliable. In the UK, blood can also be taken by nurses, healthcare assistants, doctors and some pharmacists who have completed appropriate training.

Good phlebotomists are also skilled at putting people at ease, which matters if you are nervous about needles or have veins that are hard to find.

Why might you need a phlebotomist?

You might need blood taken for:

Routine checks such as cholesterol, blood sugar (HbA1c), kidney and liver function
Thyroid, iron, vitamin D or vitamin B12 levels
Hormone tests
Monitoring a long-term condition or a medicine that needs regular blood tests
Investigating symptoms such as tiredness, weight change or recurrent infections
Some types of allergy testing
Tests requested by a GP or specialist

What happens during a blood test?

Your identity and the tests requested are checked.
A tight band (tourniquet) is placed around your upper arm to make the vein easier to find.
The skin is cleaned and a small needle is inserted, usually on the inside of the elbow.
Blood is collected into one or more small tubes. You may feel a sharp scratch.
The needle is removed, and pressure and a small plaster are applied.

The whole process typically takes under 5 minutes. Afterwards, you can usually carry on with your day as normal.

How should you prepare for a blood test?

Check if you need to fast. Most tests do not require fasting, but some do. Follow the instructions given for your specific test.
Drink water beforehand unless told otherwise. Being well hydrated makes veins easier to find.
Keep warm and wear a top with sleeves that roll up easily.
Ask about timing. Some tests, such as certain hormone tests, need to be taken at a particular time of day or point in your menstrual cycle.
Mention your medicines. Tell the person taking blood if you take blood thinners or have a bleeding disorder.
Say if you feel faint with needles. You can lie down for the test.

Are there any side effects?

Blood tests are very safe. Some people get a small bruise or feel briefly lightheaded. Pressing firmly on the site for a few minutes afterwards reduces bruising. Seek advice if the arm becomes very swollen, red or painful.

Private blood tests in Wigan, Chorley, Bolton and Horwich

At Ready Health in Standish, trained staff take blood samples in a private clinic room, and samples are sent to an accredited laboratory. When your results are back, they are reviewed and explained, and you are advised if anything needs follow-up or should be shared with your NHS GP.

Frequently asked questions

Is a phlebotomist a nurse?

Not necessarily. Many phlebotomists are specialist healthcare support workers rather than nurses, although nurses and other clinicians can also take blood.

Does having blood taken hurt?

Most people feel only a brief sharp scratch. If you are anxious, tell the person taking your blood so they can help you feel comfortable.

How long do blood test results take?

It depends on the test. Many routine results are available within a few days, while specialist tests can take longer. You will be told what to expect when your sample is taken.

What if my veins are hard to find?

Staying warm and well hydrated helps. Experienced staff can usually find a suitable vein, and a second attempt in a different place is sometimes needed.

Key takeaways

A phlebotomist is trained to take blood samples safely for laboratory testing.
Blood tests help check general health, monitor conditions and medicines, and investigate symptoms.
Most tests do not need fasting, but always follow the instructions for your test.
Drinking water and keeping warm makes the process easier.

Sources and further reading

Last reviewed: October 2026 by Shamir Patel, Independent Prescribing Pharmacist, Ready Health. This article is general information and does not replace advice from your own clinician.

To find out more about having a blood test in Standish, Wigan, see our private blood tests page, or read about our allergy testing service.