PSA — Normal Range & Interpretation

Clinical Context

Prostate-specific antigen (PSA) is a glycoprotein produced by prostate epithelial cells. Clinicians measure serum PSA to evaluate prostate health, monitor known prostate cancer, and assess men with lower urinary tract symptoms. A value above 4.0 ng/mL prompts further evaluation, though age-adjusted ranges refine interpretation in older adults.

Elevations occur with benign prostatic hyperplasia, prostatitis, prostate cancer, recent ejaculation, urinary retention, catheterization, and digital rectal examination performed before the draw. Acute prostatitis produces the sharpest rises. Finasteride and dutasteride lower PSA by roughly 50 percent after six months, so providers double reported values in men taking 5-alpha reductase inhibitors. PSA holds no clinical role in female patients.

FNPs see PSA on the boards most often in shared decision-making scenarios rather than universal screening recommendations. Expect questions citing USPSTF guidance: offer screening discussion to men ages 55 to 69, and avoid routine screening after age 70. Know that African American men and those with a first-degree relative diagnosed with prostate cancer carry higher baseline risk and warrant earlier conversations. Items also test pre-test counseling, including avoiding ejaculation and vigorous cycling for 48 hours before the draw, and recognizing that an isolated mild elevation requires repeat testing before urology referral.

Related Labs

• HbA1c — %
• ESR — mm/hr
• CRP — mg/dL
• hs-CRP — mg/L
• Uric Acid — mg/dL

Sources

• MedlinePlus
• ARUP Consult