Free Testosterone of 161.7 pg/mL: Clinical Implications and Management
A free testosterone level of 161.7 pg/mL falls within the normal range for adult men and does not indicate hypogonadism requiring testosterone replacement therapy. 1
Understanding Your Free Testosterone Level
Your free testosterone level of 161.7 pg/mL is above the lower limit of normal for adult men. According to standardized reference intervals using equilibrium dialysis methodology, the normal range for free testosterone in healthy, non-obese adult men is 66-309 pg/mL (2.5th to 97.5th percentile), with the 10th percentile at 91 pg/mL 1. Your level exceeds both the 2.5th and 10th percentile thresholds, placing you within the normal physiologic range.
Key Reference Points:
- Lower limit of normal (2.5th percentile): 66 pg/mL 1
- 10th percentile: 91 pg/mL 1
- Your level: 161.7 pg/mL
- Median (50th percentile): 141 pg/mL 1
Clinical Decision Algorithm
Step 1: Confirm Measurement Accuracy
- Ensure free testosterone was measured by equilibrium dialysis, the gold standard method, as other methods (analog immunoassays, calculated free testosterone) have significant limitations 2, 3, 4
- If measured by a different method, consider repeat testing using equilibrium dialysis for accurate assessment 3, 4
Step 2: Assess for Symptoms of Hypogonadism
Even with a normal free testosterone level, evaluate for specific symptoms:
- Primary symptoms: Diminished libido and erectile dysfunction 5, 6
- Secondary symptoms: Decreased energy, reduced muscle mass, hot flashes, gynecomastia 5
Critical point: The American College of Physicians found that testosterone therapy produces little to no benefit for physical functioning, energy, vitality, or cognition, even in men with confirmed biochemical hypogonadism 5. The primary indication for treatment is sexual dysfunction with confirmed low testosterone 5.
Step 3: Determine if Treatment is Indicated
Testosterone replacement therapy is NOT indicated in your case because:
- Your free testosterone level is normal (above the 10th percentile) 1
- The American College of Physicians explicitly recommends against testosterone therapy in men with normal or low-normal testosterone levels 5
- The European Association of Urology strongly recommends against testosterone therapy in eugonadal men (those with normal testosterone), even if symptomatic 6
If Symptoms Are Present Despite Normal Free Testosterone
Alternative Causes to Investigate:
- Sleep disorders (particularly obstructive sleep apnea) 5
- Thyroid dysfunction (hypothyroidism) 6
- Anemia 6
- Vitamin D deficiency 6
- Metabolic syndrome and cardiovascular risk factors 6
- Depression or other psychiatric conditions 5
- Medication side effects (antidepressants, opioids, corticosteroids) 6
Lifestyle Interventions:
- Weight loss through low-calorie diets if obesity is present 5, 6
- Regular physical activity and exercise 6
- Smoking cessation 6
- Reducing excess alcohol intake 6
These interventions improve sexual function and overall health without the risks associated with testosterone therapy 6.
Important Caveats About Testosterone Therapy
Why Treatment is Not Appropriate for Normal Levels:
The evidence is clear that testosterone therapy in men without confirmed biochemical hypogonadism provides minimal to no benefit:
- Small improvements in sexual function only (standardized mean difference 0.35) in men with confirmed low testosterone 5
- Minimal improvements in energy and fatigue (SMD 0.17) 5
- Less-than-small improvements in depressive symptoms (SMD -0.19) 5
- No benefit for physical functioning, cognition, or vitality 5
Potential Risks of Unnecessary Testosterone Therapy:
- Erythrocytosis (elevated hematocrit), particularly with injectable formulations 5, 6
- Cardiovascular events (uncertain risk, but potential concern) 5
- Permanent infertility through suppression of spermatogenesis 5, 6
- Fluid retention and worsening of heart failure 5, 7
- Worsening of benign prostatic hyperplasia 5, 7
- Sleep apnea exacerbation 5, 7
When to Consider Further Evaluation
Repeat testosterone testing is warranted only if:
- You develop specific symptoms of hypogonadism (diminished libido, erectile dysfunction) 5, 6
- Morning total testosterone levels are measured and found to be <300 ng/dL on two separate occasions 5, 6
- Free testosterone by equilibrium dialysis is confirmed to be <120 pg/mL (below the 2.5th percentile for young men 19-39 years) 1
For men with borderline total testosterone (280-350 ng/dL), free testosterone measurement becomes essential to distinguish true hypogonadism from low sex hormone-binding globulin-related decreases 5, 8. However, your free testosterone level of 161.7 pg/mL clearly indicates normal androgen status.
Bottom Line
No treatment is needed. Your free testosterone level is normal, and testosterone replacement therapy would expose you to potential risks without providing clinical benefit 5, 6. If you have symptoms concerning for hypogonadism, focus on identifying and treating alternative causes through the evaluation pathways outlined above 6.