Initial Dosing for Testosterone 1.62% Transdermal Gel
The FDA-approved starting dose of testosterone 1.62% gel is 40.5 mg of testosterone (2 pump actuations) applied topically once daily in the morning to clean, dry, intact skin of the shoulders and upper arms. 1
Diagnostic Prerequisites Before Initiating Therapy
Before prescribing testosterone 1.62% gel, you must confirm hypogonadism with:
- Two separate morning testosterone measurements (drawn between 8 AM and 10 AM) showing levels below 300 ng/dL 1, 2
- Presence of specific hypogonadal symptoms, particularly diminished libido and erectile dysfunction, as these are the primary symptoms that respond to treatment 2
- Measurement of LH and FSH to distinguish primary from secondary hypogonadism, which has critical treatment implications including fertility preservation 2
Critical caveat: If the patient desires fertility, testosterone therapy is absolutely contraindicated—you must use gonadotropin therapy (hCG plus FSH) instead, as exogenous testosterone suppresses spermatogenesis and causes prolonged azoospermia. 2
Exact Dosing Instructions
Starting Dose
- 40.5 mg testosterone (2 pump actuations) applied once daily in the morning 1
- Apply to shoulders and upper arms only—do not apply to abdomen, genitals, chest, armpits, or knees 1
- Apply to clean, dry, intact skin 1
Dose Adjustment Range
- Minimum dose: 20.25 mg (1 pump actuation) 1
- Maximum dose: 81 mg (4 pump actuations) 1
- Dose titration should be based on pre-dose morning serum testosterone measured at approximately 14 days and 28 days after starting treatment 1
- Target testosterone level: 450-600 ng/dL (mid-normal range) 3, 4
Application Technique and Safety Precautions
- Wash hands immediately with soap and water after application 1
- Cover application sites with clothing after gel has dried 1
- Wash application site thoroughly with soap and water before any anticipated skin-to-skin contact with another person 1
Major pitfall to avoid: Skin-to-skin transfer to women and children can cause virilization—this is why washing and covering are mandatory. 1
Monitoring Schedule
Initial Phase (First 3 Months)
- Measure testosterone levels at 14 days and 28 days after initiation to guide dose adjustment 1
- For transdermal preparations, testosterone can be measured at any time, with peak values occurring 6-8 hours after application 3
- Target mid-normal testosterone levels of 500-600 ng/dL 3, 4
Maintenance Phase
- Once stable levels are achieved, monitor testosterone every 6-12 months 2, 3
- Monitor hematocrit at each visit—withhold treatment if >54% and consider phlebotomy 2, 4
- Monitor PSA levels in men over 40 years—refer for urologic evaluation if PSA increases >1.0 ng/mL in first 6 months or >0.4 ng/mL per year thereafter 2
Expected Treatment Outcomes
Set realistic expectations with patients:
- Small but significant improvements in sexual function and libido (standardized mean difference 0.35) 2, 5
- Little to no effect on physical functioning, energy, vitality, depressive symptoms, or cognition 6, 2
- Modest quality of life improvements, primarily in sexual function domains 2
Critical decision point: If no improvement in sexual function after 12 months, discontinue treatment to prevent unnecessary long-term exposure to potential risks without benefit. 2
Cost Considerations
The annual cost for transdermal testosterone is approximately $2,135 compared to $156 for intramuscular formulations. 6 However, transdermal preparations provide more stable day-to-day testosterone levels, which may be preferred for initial treatment. 2, 3 Patient preference studies show 71% prefer topical gel over injections for convenience, ease of use, and non-staining of clothes. 6
Absolute Contraindications
Do not prescribe testosterone 1.62% gel if: