What initial test should be ordered for a male with symptoms of hypogonadism?

In the context of evaluating a male patient for symptoms of hypogonadism, the appropriate initial test to order is the measurement of total serum testosterone levels, specifically in the early morning. This is because testosterone levels exhibit diurnal variation, peaking in the early morning hours. By conducting the test at this time, healthcare providers can obtain a more accurate representation of the individual's testosterone production.

Total serum testosterone is the primary hormone that influences male sexual development and function, and low levels may confirm diagnoses of hypogonadism. If the total testosterone test shows low levels, further testing, such as measuring luteinizing hormone or free testosterone, may be warranted based on clinical judgment and results.

While there are other tests that can provide valuable information in the assessment of hypogonadism, total serum testosterone measured in the early morning is the standard initial test recommended in clinical practice.