In people with a newly elevated PSA, it will return to a normal level in 25% to 40% upon retesting.26 Among 1,686 biopsied patients in the STHLM-3 study with a PSA of 3 to 10 ng/mL, and 2 PSA tests 8 weeks apart, 283 (17%) subsequently had a PSA < 3 ng/mL. Given the clear evidence that PSA tests may normalize, it would be prudent to confirm a newly elevated PSA test before proceeding with further workup.27 The Panel also strongly supports the Choosing Wisely AUA initiative (<a href="https://www.choosingwisely.org/clinician-lists/american-urological-association-treating-elevated-psa-with-antibiotics/" target="_blank" rel="noopener">https://www.choosingwisely.org/clinician-lists/american-urological-association-treating-elevated-psa-with-antibiotics/</a>) that empiric antibiotics should not be utilized to treat an elevated PSA in an asymptomatic person.28, 29 Neither DRE nor bicycle riding appreciably alters the PSA,30, 31 and most controlled studies evaluating ejaculation suggest it either does not significantly impact or modestly increases (~10%) PSA.32 The half-life of PSA is 2 to 3 days. A repeat PSA in a few months is recommended, though it can be shortened or lengthened depending on other clinical factors. Clinicians should also recognize that urinary tract infections and instrumentation (e.g., recent bladder catheterization, prostate biopsy or cystoscopy, urinary retention) cause transient increases in PSA. PSA elevations in these settings should be repeated after appropriate time periods to allow for PSA to reach baseline level.   The definition of an elevated PSA has changed over time. The commonly cited threshold of 4 ng/mL is based on very early studies that identify the highest levels typically observed among patients thought to be free of prostate cancer. Another cited threshold of 3 ng/mL is taken from the Finnish European Randomized Study of Screening for Prostate Cancer (ERSPC) trial of prostate cancer screening that showed a significant reduction in prostate cancer deaths among patients who entered the trial between ages 55 to 69 years and were referred to biopsy based on that threshold. The knowledge that PSA generally increases with age in people without prostate cancer has led to the consensus that the threshold above which a PSA level should be considered elevated should increase with age, and that the original threshold of 4 ng/mL is too high for people in their 40s and 50s and too low for people in their 70s and 80s who have a high risk of overdiagnosis. Most studies identifying age-varying thresholds specify threshold values of 2.5 ng/mL for people in their 40s, 3.5 ng/mL for people in their 50s, 4.5 ng/mL for people in their 60s, and 6.5 ng/mL for people in their 70s.33-35 Typically, 5-alpha reductase inhibitors (5-ARIs) decrease PSA levels after at least 6 months of use, with some older studies suggesting serum PSA should be doubled for patients using 5-ARIs as an adjusted baseline.36 However, PSA kinetics vary from patient to patient, with one trial suggesting only one-third of patients on 5-ARI therapy experience a 40% to 60% decline in PSA at one year.37