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Prostate-Specific Antigen (PSA) in Plasma by Immunoassay (Quantitative)

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. PSA helps assess prostate health, detect early signs of prostate cancer, or monitor treatment progress.

Quick summary

["PSA levels can indicate prostate health or potential cancer; results guide further medical evaluation."]

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

Key facts at a glance

LOINC
41163-7
Short code
T palldm DNA Spec Ql NAA+probe
Synonyms
T palldm DNA Spec Ql NAA+probe
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
probe-amp-tar
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 in the pelvic area, or if you’re at higher risk for prostate issues (e.g., age 50+ for men with average risk, or earlier for those with family history). It may also be used during routine check-ups or after prostate procedures.

What to Expect Before the Test

No special preparation is needed, but avoid ejaculation for 2 days before testing. If you’re on medications that affect PSA levels (like finasteride or dutasteride), let your doctor know.

What the Results Mean

PSA levels vary by age, health, and other factors. A higher-than-normal result may signal prostate issues, but it doesn’t always mean cancer. Your doctor will interpret results in the context of your symptoms and medical history.

Common Causes of Elevated PSA

Elevated PSA can occur with prostate inflammation (prostatitis), benign enlargement (BPH), or prostate cancer. Other conditions, like urinary tract infections or recent prostate exams, can also temporarily raise PSA levels.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

PSA Plasma

Frequently asked questions

What does a PSA test measure?
A PSA test measures the amount of PSA protein in your blood. PSA is produced by the prostate gland and can be influenced by both healthy and unhealthy prostate conditions.
How long does it take to get PSA test results?
Results are typically available within 1–3 business days, depending on your lab and insurance processing times. Follow-up with your doctor to discuss findings.
Can diet or medications affect PSA levels?
Certain medications (like finasteride or dutasteride) can lower PSA levels. Avoid ejaculation for 2 days before testing, as this can temporarily raise PSA. Dietary factors like cruciferous vegetables may have minimal impact but discuss any concerns with your doctor.
  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