TRT Hematocrit Safety Interval Planner

Model how quickly hematocrit rises under your testosterone replacement plan, flag when you’ll breach the clinic ceiling, and set proactive reminders for lab work or phlebotomy before hemoconcentration becomes risky.

Most clinics recommend staying below 52–54% depending on comorbidities and local practice guidelines.
Average hematocrit increase per month based on recent labs or your prescriber’s forecast.
Set to your clinician’s upper limit to trigger safety actions such as dosage changes or phlebotomy.
Typical whole blood donation lowers hematocrit by 2–4 points; use 0 if donations are not part of your plan.

For informational use only. Testosterone therapy should be managed by a licensed healthcare professional with full lab interpretation.

Examples

  • 45% start, +1.2 monthly, 52% ceiling, 3-point donation drop ⇒ Reaches 52.00% in 6.00 months (~26.07 weeks), labs about every 9 weeks, donation relief lasts 2.50 months.
  • 47% start, +0.6 monthly, 54% ceiling, 0-point donation drop ⇒ Reaches 54.00% in 11.67 months (~50.69 weeks), labs about every 17 weeks, donation relief not modeled so prioritize dose adjustments.

FAQ

How do altitude or sleep apnea affect this projection?

Higher altitude and untreated sleep apnea both increase erythropoietin stimulation. If either applies, increase the monthly rise input to stress-test faster hematocrit climbing.

Can I model dose reductions instead of donations?

Yes. Lower the monthly rise figure to reflect the expected response to a dose change or longer injection interval and rerun the calculation.

What if I microdose testosterone daily?

Microdosing often flattens hematocrit drift. Enter a smaller monthly rise based on prior labs or your clinician’s estimate to see how it delays hitting the ceiling.

Does the planner consider ferritin depletion from frequent donations?

Ferritin is not modeled. Track ferritin and iron saturation separately with your provider to avoid deficiency during ongoing blood donation schedules.

Additional Information

  • Monthly rise is modeled as linear; update the input whenever protocol changes, aromatase inhibitors, or lifestyle shifts alter erythropoiesis.
  • Donation drop assumes a consistent reduction per phlebotomy; monitor actual post-draw labs and adjust the drop value accordingly.
  • Lab cadence recommendation converts time-to-ceiling into practical week intervals so you can align with insurance-covered draws and clinical follow-up.
  • Always coordinate with a licensed clinician; calculator outputs complement but do not replace medical judgment.

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