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

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

This test measures the level of prostate-specific antigen (PSA), a protein produced by both healthy and cancerous prostate cells. It helps assess prostate health and detect early signs of prostate cancer.

Quick summary

["PSA tests are used to monitor prostate health and screen for potential cancer, though they are not definitive on their own."]

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

Key facts at a glance

LOINC
87388-5
Short code
PSV Spec Ql Cult
Synonyms
PSV Spec Ql Cult
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
organism-specific-culture
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 frequent urination, pain during urination, or if you’re at higher risk for prostate issues due to age, family history, or other medical conditions. It’s also used as part of routine screening for men over 50 or those with specific risk factors.

What to Expect Before the Test

No special preparation is needed, but you may be asked to avoid ejaculation for 2–3 days before testing to get a more accurate result. Wear comfortable clothing and plan to stay for about 15 minutes while blood is drawn.

What Happens During the Test

A healthcare provider will collect a small blood sample from a vein in your arm using a needle. You may feel a brief pinch, but it’s usually over quickly. The sample is then sent to a lab for PSA measurement.

What the Results Mean

PSA levels vary by age, health, and other factors. While higher levels can signal prostate concerns, they don’t always mean cancer. Your doctor will discuss results in the context of your medical history and symptoms.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

PSA Screen

Frequently asked questions

What does a PSA test detect?
A PSA test detects PSA in your blood, which can indicate prostate inflammation, infection, benign prostatic hyperplasia (BPH), or prostate cancer. However, it’s not a perfect test—false positives and negatives can occur, so further evaluation (like a biopsy) may be needed if results are abnormal.
How often should I get a PSA test?
The frequency depends on your age, health, and risk factors. The U.S. Preventive Services Task Force recommends discussing PSA screening with your doctor, especially if you’re over 50 or have a family history of prostate cancer.
Can lifestyle changes affect PSA levels?
Yes, certain activities like ejaculation, exercise, or even sexual arousal can temporarily raise PSA levels. Avoiding these for a few days before testing can help get a more stable result.
  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