Testosterone test

Covers how testosterone testing works, including total vs. free testosterone, timing, and factors that can skew results. Learn what the numbers can (and can’t) tell you about symptoms, performance, and whether further labs or TRT evaluation make sense.

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Function Health testosterone results: What “out of range” really means and what to do next

Function Health testosterone results: What “out of range” really means and what to do next

Dr. Susan Carter, MD avatar
Dr. Susan Carter, MD: Endocrinologist & Longevity Expert
Feb 09, 2026 · 13 min read

An “out of range” testosterone result means your value fell outside that lab’s reference interval, not that you have hypogonadism. The next step is to repeat a morning total testosterone and add confirmatory labs (free testosterone with SHBG, plus LH/FSH) interpreted alongside symptoms before deciding on treatment. “When a lab report says ‘normal’, it mostly ...

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