Creatine Supplementation Does Not Affect PSA Levels
Daily creatine supplementation at 5-10 g does not alter PSA test results and should not interfere with prostate cancer screening or monitoring. The available evidence demonstrates no impact of creatine on PSA concentrations in men, including those with prostate cancer.
Evidence Supporting No Effect on PSA
The most recent and highest-quality evidence comes from a 2025 randomized controlled trial that examined creatine supplementation (combined with resistance training) in prostate cancer patients undergoing androgen deprivation therapy 1. This study found no adverse effects from creatine supplementation and no indication that creatine altered PSA levels or prostate-related outcomes.
A 2019 trial protocol examining creatine supplementation in the same patient population similarly identified no concerns regarding PSA interference 2. These studies specifically evaluated creatine in men with prostate cancer—the population most sensitive to PSA changes—and found no PSA-related issues.
Understanding PSA Variability
The guideline literature extensively documents factors that do affect PSA levels, which is relevant context for understanding what creatine does not do:
- Testosterone therapy causes modest PSA increases of approximately 0.30-0.43 ng/mL 3, 4
- 5α-reductase inhibitors (finasteride, dutasteride) decrease PSA by approximately 50% within 6-12 months 5
- Prostatitis, BPH, recent ejaculation, and prostate manipulation can elevate PSA 6
- Laboratory variability itself can cause 20-25% fluctuation 6
Notably, creatine supplementation is not mentioned in any major guidelines addressing PSA interpretation or factors affecting PSA levels 7, 8, 3, 4, 5, 9, 6, despite these guidelines comprehensively cataloging substances and conditions that interfere with PSA testing.
Clinical Implications
For men taking creatine supplements:
- Continue routine PSA screening according to standard guidelines without adjustment for creatine use
- No need to discontinue creatine before PSA testing
- Standard PSA thresholds apply: PSA >4.0 ng/mL warrants urological evaluation 3
- Normal PSA kinetics interpretation: Increases >1.4 ng/mL over 3-6 months or velocity >0.75 ng/mL/year remain concerning regardless of creatine use 4, 6
Important Caveat
While creatine does not affect PSA levels used for screening, emerging research suggests that creatine metabolism may play a role in prostate cancer cell biology 10. However, this relates to intracellular cancer cell metabolism, not serum PSA concentrations used for clinical testing. The cyclocreatine analog (not standard creatine supplements) has shown anti-tumor effects in preclinical models 10, but this is mechanistically distinct from any effect on PSA testing.
Bottom line: Proceed with PSA testing and interpretation using standard clinical guidelines without concern for creatine supplementation interference. The 5-10 g daily dose range does not require any special consideration in PSA screening protocols.