PSA
Prostate-Specific Antigen (PSA) is a protein produced by the prostate gland. This test measures PSA levels in the blood and is primarily used to screen for prostate cancer.
Category: Tumor Markers
Also known as: psa, prostate specific antigen, prostate-specific antigen, total psa
Reference range: 0–4 ng/mL (Source: ABIM)
Standard unit: ng/mL
High values may indicate
High PSA levels may indicate prostate cancer, benign prostatic hyperplasia (BPH), prostatitis, or recent urinary tract procedures.
Low values may indicate
Low PSA levels are generally normal and indicate a lower likelihood of prostate disease.
Frequently asked questions
- What is a normal PSA level?
- A typical reference range for PSA is 0–4 ng/mL (source: ABIM). Reference ranges vary by laboratory, age, and sex, so always compare against the range on your own lab report.
- What units is PSA measured in?
- PSA is most commonly reported in ng/mL. Labs in different countries may use other units — you can convert between them with BloodId's blood test unit converter.
- Where do PSA reference ranges come from?
- BloodId uses ABIM standard reference ranges and educational information from MedlinePlus (see our methodology). Reference ranges still vary by lab, age, and sex, so always compare against your own report.
- Can I track PSA over time?
- Yes. Upload results from any lab and BloodId charts your PSA over time against its reference range, so you can see whether the trend is rising, falling, or stable.