A blood test usually involves the phlebotomist taking a blood sample from a blood vessel in your arm. The usual place for a sample is the inside of the elbow or wrist, where the veins are relatively close to the surface.
If you have been asked to have a fasting blood test, please drink plenty of water, but do not eat or drink anything else after midnight the night before the test.
Blood samples are sent to the laboratory for analysis and results should be available through Reception after 2:30p.m. approximately one week later.
You can find out more about blood tests, their purpose and the way they are performed on the NHS Choices website.