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Prostate-Specific Antigen (PSA) by Immunoassay (Screening)

Published: August 9, 2026Updated: August 16, 2026

This blood test measures the level of prostate-specific antigen, a protein produced by the prostate gland. It helps assess the risk of prostate cancer or other prostate-related conditions.

Quick summary

["PSA levels can guide discussions about prostate health and potential follow-up tests."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
24020-0
Short code
Gp B Strep Ag Ur Ql
Synonyms
Gp B Strep Ag Ur Ql
Category
coagulation
Sample
urine
Container
Sterile urine container
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
10 mL
Stability
Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

Why This Test Might Be Ordered

Your doctor may recommend this test if you have symptoms like frequent urination, pain during urination, or if you’re at higher risk for prostate issues due to age, family history, or other health concerns. It’s also used as a baseline or follow-up for men with known prostate conditions.

What to Expect Before the Test

No special preparation is needed, but avoid ejaculation for 2–3 days before testing. Drink plenty of water the day of your visit to help prepare your blood sample.

What the Test Results Mean

Results are interpreted by your healthcare provider based on your age, symptoms, and overall health. Elevated levels may raise concerns, but they don’t always mean cancer. Follow-up tests or discussions with your doctor are important.

Common Reasons for Abnormal Results

High PSA levels can be caused by benign prostate enlargement, infections, or inflammation, not just cancer. Low levels may indicate an enlarged prostate or other conditions, but they don’t rule out prostate cancer entirely.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

PSA Screening

Frequently asked questions

How often should I get this test?
The frequency depends on your age, symptoms, and risk factors. Men under 50 typically don’t get routine PSA screenings unless advised by a doctor. Those over 50 may discuss testing with their provider, especially if they have a family history of prostate cancer.
Can PSA levels change over time?
Yes, PSA levels can fluctuate due to factors like age, recent ejaculation, prostate inflammation, or medications. Your doctor will consider these factors when interpreting results.
What if my PSA level is in the normal range?
A normal PSA level doesn’t guarantee you don’t have prostate cancer. It’s one piece of information your doctor uses alongside other tests or symptoms to make a full assessment.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy