Hematocrit & PSA on testosterone
Also known as:
Testosterone safety monitoring, red cell count, prostate-specific antigen
The two safety labs every man on testosterone needs, and what the thresholds mean.
Written and reviewed by Farhan Tahir, MD · Last reviewed
VIDEO LESSON
Why they matter
Testosterone stimulates red blood cell production, so hematocrit can climb high enough to thicken the blood. It can also raise PSA and may unmask existing prostate disease.
Monitoring schedule
• Hematocrit at baseline, at 3 to 6 months, then yearly
• PSA at baseline and at 3 to 12 months in men 55 to 69, or 40 to 69 at higher risk, then per prostate screening guidance
• Symptoms, testosterone level and side effects at each review
Action thresholds
• Hematocrit above 54%: pause or reduce therapy, and look for sleep apnea and other causes
• PSA rise greater than 1.4 ng/mL within 12 months, a confirmed PSA above 4.0 ng/mL or an abnormal exam: urology referral
Good to know
Injections cause larger rises in hematocrit than gels. Hydration does not fix a high hematocrit; dose changes do.
Key studies and references
Educational content only, written and reviewed by Farhan Tahir, MD. It does not replace individual medical advice. For sudden chest pain, trouble breathing or stroke symptoms, call 911.
AT A GLANCE
Test type
Bone & safety
Also known as
Testosterone safety monitoring, red cell count, prostate-specific antigen
Reviewed by
Farhan Tahir, MD
Questions about your own care?
Dr. Tahir’s team offers consults through Youthful Medicine.
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