How do I order bioidentical testosterone for an adult male with documented low testosterone and symptoms (decreased libido, fatigue, loss of muscle mass, mood changes) after confirming no contraindications (active prostate or breast cancer, prostate‑specific antigen >4 ng/mL without urologic evaluation, untreated severe sleep apnea, uncontrolled hypertension, hematocrit >50%)?

How to Order Bioidentical Testosterone

For an adult male with documented hypogonadism (two morning testosterone measurements <300 ng/dL) and qualifying symptoms (diminished libido, erectile dysfunction), order transdermal testosterone gel 1.62% at 40.5 mg applied once daily to the shoulders and upper arms as first-line therapy, targeting mid-normal serum levels of 500–600 ng/dL. 1, 2

Confirm the Diagnosis Before Ordering

• Verify that two separate fasting morning total testosterone measurements (8–10 AM) are both <300 ng/dL to establish biochemical hypogonadism; a single measurement is insufficient due to diurnal variation and assay variability. 1, 3, 4
• Confirm the patient has diminished libido or erectile dysfunction as primary symptoms, because these are the only complaints that reliably improve with testosterone therapy (standardized mean difference ≈0.35). 5, 1
• Measure LH and FSH after confirming low testosterone to distinguish primary (elevated gonadotropins) from secondary (low/normal gonadotropins) hypogonadism; this distinction is critical for treatment selection and fertility counseling. 1, 3, 4

Exclude Absolute Contraindications

• Do not order testosterone if the patient has active prostate or breast cancer, PSA >4 ng/mL without urologic evaluation (or >3 ng/mL in African-American men or those with a first-degree relative with prostate cancer), hematocrit >50%, untreated severe obstructive sleep apnea, uncontrolled heart failure, myocardial infarction or stroke within the past 6 months, or active desire for fertility preservation. 2, 3, 4
• If the patient desires fertility, order gonadotropin therapy (hCG plus FSH) instead of testosterone, because exogenous testosterone causes prolonged azoospermia. 1, 4

Choose the Formulation

First-Line: Transdermal Testosterone Gel

• Order testosterone gel 1.62% at 40.5 mg (two pump actuations or one 40.5 mg packet) applied once daily in the morning to clean, dry, intact skin of the shoulders and upper arms. 1, 2
• Transdermal gel is preferred because it provides stable day-to-day testosterone levels and carries a lower risk of erythrocytosis (≈15%) compared with injectable formulations (≈44%). 1, 2
• Instruct the patient to wash hands immediately with soap and water after application, cover the application site with clothing after the gel dries, and wash the application site thoroughly before any skin-to-skin contact to prevent secondary exposure to women and children. 2

Alternative: Intramuscular Testosterone Injections

• If cost is a primary concern or the patient prefers injections, order testosterone cypionate or enanthate 100–200 mg intramuscularly every 2 weeks (or 50–100 mg weekly for more stable levels). 1, 6, 3
• Injectable testosterone is more economical (annual cost ≈$156 vs. ≈$2,135 for gel) but produces supraphysiologic peaks 2–5 days post-injection and carries a higher erythrocytosis risk. 1
• For injectable therapy, measure testosterone levels midway between injections (days 5–7 for weekly dosing, days 7–10 for bi-weekly dosing) to assess average exposure rather than peak or trough values. 1

Obtain Baseline Laboratory Tests

• Measure baseline hematocrit or hemoglobin before initiating therapy; hematocrit >50% is an absolute contraindication. 1, 3, 4
• Obtain PSA and perform digital rectal examination in men >40 years; PSA >4.0 ng/mL (or >3.0 ng/mL in high-risk groups) requires urologic evaluation and documented negative prostate biopsy before starting therapy. 1, 3, 4
• Measure fasting glucose and HbA1c to screen for diabetes, and obtain a lipid profile as part of baseline metabolic assessment. 1

Set Realistic Expectations

• Explain that testosterone therapy produces small but significant improvements in sexual function and libido only (standardized mean difference ≈0.35), with little to no benefit for energy, vitality, physical functioning, depressive symptoms, or cognition. 5, 1, 7
• Clarify that fatigue, low energy, mood changes, and "brain fog" do not improve meaningfully with testosterone therapy, even when hypogonadism is biochemically confirmed. 5, 7
• Inform the patient that if sexual function does not improve within 12 months, testosterone should be discontinued to avoid unnecessary exposure to potential risks without benefit. 1

Monitoring Protocol

Initial Follow-Up (2–3 Months)

• Measure serum testosterone (midway between injections for injectable formulations, anytime after 2–3 months for transdermal gel), targeting mid-normal levels of 500–600 ng/dL. 1, 3, 4
• Repeat hematocrit; withhold testosterone if hematocrit rises >54% and consider therapeutic phlebotomy in high-risk patients. 1, 3, 4
• Re-check PSA in men >40 years. 1, 3, 4
• Assess clinical response, particularly improvement in sexual function and libido. 1

Ongoing Monitoring (Every 3–6 Months During Year 1, Then Annually)

• Repeat testosterone, hematocrit, PSA, and digital rectal examination at each visit. 1, 3, 4
• Refer to urology if PSA increases >1.0 ng/mL within the first 6 months or >0.4 ng/mL per year thereafter, or if a palpable prostate nodule or induration develops. 1, 3, 4

Dose Adjustment

• If symptoms persist with sub-optimal testosterone levels at the 2–3 month follow-up, increase the dose: for gel, titrate up to a maximum of 81 mg daily (four pump actuations or two 40.5 mg packets); for injections, increase to 200 mg every 2 weeks or 100 mg weekly. 1, 2
• If clinical response is adequate, no dose adjustment is needed even if testosterone levels are in the low-normal range. 1

Common Pitfalls to Avoid

• Do not diagnose hypogonadism on a single testosterone measurement or on symptoms alone; require two morning values <300 ng/dL plus specific sexual symptoms. 1, 3, 4
• Do not omit LH and FSH testing after confirming low testosterone; the distinction between primary and secondary hypogonadism directs therapy and fertility counseling. 1, 3, 4
• Do not initiate testosterone without confirming the patient does not desire fertility, as exogenous testosterone causes prolonged azoospermia. 1, 4
• Do not prescribe testosterone for weight loss, general energy enhancement, or athletic performance, as these are not evidence-based indications. 1, 7
• Approximately 50% of men on testosterone therapy never have their levels re-checked, representing a significant safety gap; ensure adherence to the monitoring protocol. 1