Unbound prostate-specific antigen; interpreted with total PSA.
What it is
Free PSA is the portion of PSA not complexed to proteins. It is used with total PSA to form a free/total ratio.
Why it matters
Never interpret free PSA without total PSA and clinical prostate pathways.
This guide is educational only and cannot diagnose you. Discuss results, especially anything outside your laboratory’s reference interval, or that does not match how you feel, with a GP or other appropriately qualified clinician.
How it affects the body
PSA forms are produced by prostate tissue; levels rise with several benign and malignant processes.
For athletes
Cycling and ejaculation can affect PSA transiently: follow lab timing advice before testing.
