Prostate-Specific Antigen (PSA) in Serum
This test measures the amount of prostate-specific antigen, a protein produced mainly by the prostate gland, in your blood. It helps evaluate prostate health and detect potential issues like benign prostatic hyperplasia (BPH) or prostate cancer.
["PSA levels can guide discussions about prostate health, but they’re not definitive on their own."]
Key facts at a glance
- LOINC
- 47125-0
- Short code
- Primidone Gast-sCnc
- Synonyms
- Primidone Gast-sCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84484
- SNOMED
- 302774002
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Might Be Ordered
Your doctor may recommend a PSA test if you have symptoms like urinary difficulties, pain in the pelvic area, or if you’re at higher risk for prostate cancer due to age, family history, or other factors. It’s also sometimes used as part of routine screening for men over 50 or those with risk factors.
What to Expect Before the Test
No special preparation is needed, but you may be asked to avoid ejaculation for 2–4 days before the test if it’s part of a more detailed evaluation. A simple blood draw is performed in a clinic or lab.
What the Results Mean
PSA levels alone don’t diagnose prostate cancer—they’re often used alongside other tests and clinical findings. Very high levels may signal cancer, but they can also be raised by infections, inflammation, or other conditions. Discuss your results with your doctor for interpretation.
Common Causes of Elevated PSA
Elevated PSA can result from prostate inflammation (prostatitis), an enlarged prostate (BPH), or prostate cancer. Other conditions, like urinary tract infections or recent ejaculation, can also temporarily raise levels.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
PSA Level
Frequently asked questions
How often should I get a PSA test?
What if my PSA level is normal but I have prostate symptoms?
Can diet or supplements affect PSA levels?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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 17, 2026. · Read our editorial policy