From the Guidelines
For individuals on testosterone therapy, labs should be checked every 6-12 months while on testosterone therapy, as recommended by the American Urological Association guideline 1.
Key Monitoring Parameters
The monitoring should include:
- Total testosterone levels
- Complete blood count to monitor for polycythemia
- Lipid panel
- Liver function tests
- PSA levels, especially in men over 40 years of age, to minimize the risk of prescribing testosterone therapy to men with occult prostate cancer 1
- Estradiol levels, as sometimes necessary
Timing of Blood Draws
The timing of blood draws is crucial:
- For injectable testosterone, labs should be drawn midway between injections (3-4 days after injection for weekly dosing)
- For daily applications like gels or patches, testing can occur at any consistent time
Additional Considerations
More frequent monitoring may be needed for those with pre-existing conditions like cardiovascular disease, liver problems, or if dose adjustments are made. Adjustments to testosterone dosing should only be made based on both lab results and clinical symptoms, not solely on numbers. It is essential to follow the American Urological Association’s Early Detection of Prostate Cancer Guideline for PSA testing in patients on testosterone therapy 1. Regular monitoring helps ensure testosterone levels remain in the target range while minimizing potential side effects such as excessive red blood cell production, liver strain, or cardiovascular complications. The method of testosterone replacement should be individualized for each patient, with transdermal testosterone preparations suggested for most hypogonadal men due to their convenience and ability to produce normal serum testosterone concentrations 1.
From the FDA Drug Label
Monitor serum testosterone, prostate specific antigen (PSA), hemoglobin, hematocrit, liver function tests and lipid concentrations periodically. (5.1,5.3,5.9,5.13) The dose should be titrated based on the pre-dose morning serum testosterone concentration at approximately 14 days and 28 days after starting treatment or following dose adjustment. Additionally, serum testosterone concentration should be assessed periodically thereafter. (2. 1)
The labs should be followed periodically, with specific assessments at:
- 14 days after starting treatment
- 28 days after starting treatment
- After dose adjustments This includes monitoring of serum testosterone, prostate specific antigen (PSA), hemoglobin, hematocrit, liver function tests, and lipid concentrations 2.
From the Research
Monitoring Testosterone Replacement Therapy
To ensure the benefits of testosterone replacement therapy are optimized and risks are minimized, regular monitoring is necessary. This includes:
- Evaluation of symptoms and side effects 3
- Measurement of testosterone and hematocrit levels 3
- Assessment of prostate-specific antigen (PSA) levels, particularly in men at risk of prostate cancer 4, 3
- Monitoring of blood pressure, lipid profile, and liver enzymes 5, 6
Frequency of Lab Tests
The frequency of lab tests may vary depending on individual patient needs and risk factors. However, some studies suggest:
- Testosterone and PSA levels should be assessed every 6-12 months 4
- Hematocrit and liver function tests should be monitored regularly, especially in patients at risk of erythrocytosis or liver damage 5, 6
- Lipid profiles and blood pressure should be checked regularly to assess the risk of cardiovascular complications 5, 6
Patient Selection and Risk Factors
Careful patient selection and assessment of risk factors are crucial before initiating testosterone replacement therapy. This includes: