
Facing the truth: My experience with testosterone replacement therapy side effects

Dr. Bruno Rodriguez, DPT, CSCS: Strength, Recovery, and Physical Therapy Expert
Aug 06, 2025 · 12 min read
Testosterone replacement therapy can cause predictable side effects—most notably testosterone-driven increases in red blood cell production that push hematocrit above 54% in about 18–20% of men, a threshold linked to thicker blood and higher clot/cardiovascular risk when not monitored. Here’s how the main risks (blood, fluid retention, hair/skin changes, and hormone shutdown) happen and what ...