What treatment is recommended for a patient with total testosterone of 672 and free testosterone of 4.3?

Normal Testosterone Levels: No Treatment Needed

A total testosterone level of 672 ng/dL and free testosterone of 4.3 ng/dL are within normal range and do not require testosterone replacement therapy.

Interpretation of Results

• Normal total testosterone range for adult men is 300-800 ng/dL in most laboratories 1
• The patient's total testosterone level (672 ng/dL) falls well within this normal range
• Free testosterone is the most accurate measure of testosterone bioavailability 2
• When evaluating testosterone levels clinically, measurement of morning serum free testosterone is essential 1

Clinical Decision Making

When assessing testosterone levels:

1. Normal levels (current case):

   • Total testosterone 672 ng/dL → within normal range (300-800 ng/dL)
   • Free testosterone 4.3 ng/dL → within normal range
   • Action: No treatment indicated

2. Low testosterone scenario:

   • If total testosterone were <300 ng/dL with symptoms
   • If free testosterone were low by equilibrium dialysis
   • Action: Consider treatment after confirming with repeat morning measurements

Testosterone Replacement Considerations

Testosterone replacement therapy is only indicated when:

• Morning total testosterone levels are consistently below 300 ng/dL 3
• Free testosterone levels are frankly low on at least 2 separate assessments 1
• Patient has symptoms of hypogonadism (decreased energy, libido, muscle mass, etc.) 1
• Hypogonadism workup has been completed to rule out other etiologies 1

Monitoring Recommendations

For patients with borderline results:

• Repeat testosterone measurements in the morning (between 8-10 AM) 1, 2
• Ensure measurements are taken on two separate days 3
• Use reliable assays for measurement 4

Important Caveats

• Testosterone levels can fluctuate based on time of day, stress, and other factors
• Obesity can affect sex hormone-binding globulin levels, potentially leading to normal free testosterone despite low total testosterone 1
• Age-related hypogonadism ("late-onset hypogonadism") is not an FDA-approved indication for testosterone therapy 3
• Initiating testosterone therapy when levels are normal can lead to unnecessary risks including erythrocytosis, cardiovascular effects, testicular atrophy, and infertility 2

In this case, with both total and free testosterone levels within normal range, testosterone replacement therapy is not indicated and could potentially cause harm without providing benefit.