At what time should testosterone be measured?

From the Guidelines

Testosterone levels should be measured in the morning, between 8 AM and 10 AM, to accurately assess total testosterone concentration and free testosterone levels by equilibrium dialysis, as recommended in patients with signs and symptoms of hypogonadism, including those with obesity 1.

Key Considerations

• The timing of testosterone measurement is crucial, as levels can vary throughout the day, and morning levels are typically the highest.
• For patients receiving testosterone injections, levels should be measured midway between injections, targeting a mid-normal value (500-600 ng/dL) 1.
• For patients receiving transdermal preparations, levels can be measured at any time, with the understanding that peak values occur 6 to 8 hours after application of the patch, and that testosterone concentrations can vary substantially with gel use, although not in a predictable way 1.

Administration Timing

• Testosterone replacement therapy can be administered at various times, but morning application is often preferred to mimic natural patterns and may help with energy levels throughout the day.
• Consistency in timing is important, as this helps maintain stable hormone levels.
• If side effects like insomnia occur, consider adjusting the timing in consultation with your healthcare provider.

Monitoring and Follow-up

• Testosterone levels should be tested 2 to 3 months after treatment initiation, and/or after any dose change, to determine that normal serum testosterone concentrations are being achieved 1.
• Once stable levels are confirmed on a given dose, monitoring every 6 to 12 months is typically sufficient.

From the Research

Testosterone Administration

The optimal time for testosterone administration is not explicitly stated in the provided studies. However, the studies discuss various aspects of testosterone replacement therapy, including its safety, efficacy, and different modes of administration.

Modes of Testosterone Administration

• Transdermal testosterone delivery, including patches and gels, is discussed in 2 and 3. These studies suggest that transdermal administration delivers testosterone at a controlled rate into the systemic circulation, avoiding hepatic first pass and reproducing the diurnal rhythm of testosterone secretion.
• Testosterone gels are also discussed in 4 and 3, which highlight their convenience, ease of administration, and flexible dosing regimens.
• Subcutaneous administration of testosterone esters is discussed in 5, which suggests that this route is easier to self-administer and has the potential to improve patient adherence.
• Testosterone injections are discussed in 5 and 6, which highlight their potential risks, including cardiovascular events, hospitalizations, and deaths.

Safety and Efficacy

• The safety and efficacy of testosterone gel in the treatment of male hypogonadism are discussed in 3, which suggests that testosterone gels are as efficacious as patches and injectable forms in their effects on sexual function and mood.
• The comparative safety of testosterone dosage forms is discussed in 6, which suggests that testosterone injections are associated with a greater risk of cardiovascular events, hospitalizations, and deaths compared with gels.
• The pharmacokinetics and safety of subcutaneous testosterone therapy are discussed in 5, which suggests that this route results in comparable pharmacokinetics and mean serum testosterone levels to intramuscular administration.