From the Guidelines
Physiological doses of testosterone gel typically range from 50 to 100 mg per day, which aims to restore testosterone levels to the normal physiological range of 300-1000 ng/dL in men with hypogonadism. These doses are designed to mimic natural testosterone production and are applied daily to clean, dry skin, usually on the shoulders, upper arms, or abdomen. Supraphysiological doses exceed 100 mg per day and result in testosterone levels above the normal physiological range. According to the study by Bhasin et al. 1, the typical dose range for testosterone gel is 50-100 mg per day, which is consistent with the goal of restoring normal physiological testosterone levels.
The normal total testosterone range for adult men is 300 to 800 ng/dL in most laboratories, as stated in the study 1. Testosterone replacement therapy should aim to restore testosterone levels to this normal range, rather than exceeding it. The use of supraphysiological doses can increase the risk of adverse effects such as polycythemia, cardiovascular complications, mood swings, and potential liver toxicity.
When using testosterone gel, it's essential to follow proper application and monitoring procedures to ensure safety and efficacy. This includes washing hands thoroughly after application, allowing the gel to dry completely before dressing, and avoiding skin-to-skin contact with others at the application site to prevent testosterone transfer. Regular monitoring of testosterone levels, complete blood count, prostate-specific antigen, and liver function is also crucial during treatment, as recommended in the study 1.
The gel formulation allows for steady absorption through the skin, providing more consistent hormone levels compared to some other testosterone delivery methods. However, it's crucial to individualize the method of testosterone replacement for each patient, considering factors such as personal preference, disease management skills, and potential side effects, as discussed in the study 1.
In summary, physiological doses of testosterone gel should be used to restore normal testosterone levels in men with hypogonadism, and supraphysiological doses should be avoided due to the increased risk of adverse effects. Proper application, monitoring, and individualization of treatment are essential to ensure safe and effective testosterone replacement therapy.
From the Research
Physiological and Supraphysiological Doses of Testosterone Gel
- A physiological dose of testosterone gel is considered to be a dose that restores serum testosterone concentrations to normal physiologic levels, which is generally defined as a range of 300-1140 ng/dL 2.
- In the study by 2, a novel testosterone 2% gel was administered once daily to the front and inner thighs at starting doses of 40 mg/d, with dose adjustments in 10-mg increments between 10 and 70 mg/d.
- The study found that 100 (77.5%) patients achieved serum total testosterone concentrations within the normal physiologic range (≥ 300 and ≤ 1140 ng/dL) on day 90, with a mean testosterone concentration of 438.6 ± 162.5 ng/dL.
- A supraphysiological dose of testosterone gel is considered to be a dose that results in serum testosterone concentrations above the normal physiologic range, which can increase the risk of adverse effects.
- In the study by 2, only 2 patients (1.6%) had serum testosterone C(max) levels above 1800 ng/dL, indicating that the 2% testosterone gel was effective in restoring normal testosterone levels without causing supraphysiological levels in most patients.
Comparison of Testosterone Gel Formulations
- Different testosterone gel formulations have been developed, including a 1% hydroalcoholic gel and a 2% gel, which have been shown to be effective in restoring normal testosterone levels in hypogonadal men 3, 4, 5.
- The 2% testosterone gel has been shown to have a favorable pharmacokinetic profile, with rapid absorption and a high bioavailability of approximately 9-14% 6.
- The choice of testosterone gel formulation and dose depends on individual patient needs and response to treatment, and should be guided by serum testosterone levels and clinical symptoms.
Dosing and Administration
- Testosterone gel is typically administered once daily, with the dose adjusted based on serum testosterone levels and clinical response.
- The dose of testosterone gel can be adjusted in increments of 10-25 mg/d, depending on the formulation and individual patient needs.
- It is essential to monitor serum testosterone levels and adjust the dose accordingly to avoid supraphysiological levels and minimize the risk of adverse effects.