Research

Hormonal

Testosterone replacement therapy increases hemoglobin and hematocrit levels in older hypogonadal men, requiring monitoring for polycythemia.

Testosterone therapy will increase your red blood cell count (hemoglobin). This is a known effect. You need regular blood tests to monitor this. If your levels get too high, your doctor may need to adjust your dose or perform phlebotomy (blood removal) to keep you safe.

GoodSupportsHIGH confidence
Hemoglobin increased significantly with testosterone by 3 months and was sustained throughout the study... Four men (24%) in the testosterone group developed elevations in hematocrit >52%.
Rahmawati Sih et al. · The Journal of Clinical Endocrinology & Metabolism · 1997

Why this rating

RCT design, clear statistical significance, but small sample size limits generalizability of side effect rates.

Source

Testosterone Replacement in Older Hypogonadal Men: A 12-Month Randomized Controlled Trial

Rahmawati Sih et al. · The Journal of Clinical Endocrinology & Metabolism · 1997

DOI 10.1210/jcem.82.6.3988

rct · n=32Cited 895×
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DOI resolved against Crossref · corpus check 2026-06-10

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