What is the recommended starting dose of injectable testosterone for a perimenopausal woman?

Starting Dose for Injectable Testosterone in Perimenopausal Women

Injectable testosterone is not recommended as first-line therapy for perimenopausal women; transdermal testosterone at 10 mg daily is the evidence-based starting dose, as injections cause supraphysiological levels and are explicitly not recommended for women. 1

Why Injections Are Contraindicated

• Injections and pellets produce supraphysiological testosterone levels in women and carry unacceptable safety risks, making them inappropriate regardless of dose reduction attempts 1
• The pharmacokinetics of injectable testosterone formulations (designed for male physiology) create peak levels far exceeding the premenopausal female physiologic range of 0.3-1.7 nmol/L, even when doses are reduced 2
• No injectable testosterone preparation has been studied or approved for use in women, and all available data explicitly recommend against their use 1

Recommended Approach: Transdermal Testosterone

First-Line Dosing

• Start with 10 mg of 1% testosterone gel applied transdermally daily to achieve serum testosterone levels within the normal premenopausal range (approximately 3.2 nmol/L or 92 ng/dL) 2
• Apply the gel in a thin layer over approximately 15 cm² on the outside of the thigh each morning 2
• This dose produces stable, physiologic testosterone levels without the dangerous peaks seen with injections 2

Dose Titration

• If 10 mg daily is insufficient after 2-3 months, increase to 20 mg daily, which produces mean testosterone levels of approximately 7.2 nmol/L 2
• Doses above 20 mg daily show minimal additional benefit (30 mg produces only 7.5 nmol/L, barely higher than 20 mg) 2
• Monitor testosterone levels to ensure they remain within the premenopausal physiologic range and avoid supraphysiological levels 1

Critical Safety Considerations

Concomitant Estrogen Requirement

• Testosterone therapy without concomitant estrogen cannot be recommended in perimenopausal women due to lack of safety evidence 3
• Most clinical trials demonstrating efficacy and safety used testosterone in combination with adequate estrogen replacement 3, 4
• Ensure the patient is adequately estrogenized before initiating testosterone therapy 4

Monitoring Protocol

• Measure testosterone levels only to detect supraphysiological levels, not to diagnose deficiency, as available assays lack accuracy at female physiologic ranges 3
• Assess subjective sexual response, desire, and satisfaction at each follow-up 3
• Monitor for androgenic side effects including hirsutism and acne 3
• Long-term cardiovascular, breast cancer, and cognitive safety data are lacking, limiting treatment duration recommendations 1

Duration of Therapy

• Use the lowest effective dose for the shortest duration that meets treatment goals 3
• Clinical trial data support safety for up to 2 years, but longer-term safety is unknown 4, 1

Common Pitfalls to Avoid

• Never use testosterone products formulated for men (including reduced doses of male injections), as they carry excessive dosing risk and produce supraphysiological levels 3, 1
• Avoid custom-compounded products when possible, as dosing consistency is inferior to government-approved preparations 3
• Do not initiate testosterone therapy without first ruling out other causes of sexual dysfunction (physical factors, psychosocial factors, medications) 3
• Testosterone is contraindicated in women with breast or uterine cancer, cardiovascular disease, or liver disease 3
• Do not use oral testosterone formulations due to first-pass hepatic effects and adverse lipid changes 3

Clinical Context

The question specifically asks about injectable testosterone, but the evidence unequivocally recommends against this route in women 1. While low-dose oral methyltestosterone (1.25-2.5 mg) combined with esterified estrogen has historical use 5, transdermal preparations are strongly preferred due to superior safety profiles and avoidance of hepatic first-pass metabolism 3, 2. The only appropriate answer is to redirect to transdermal therapy at 10 mg daily as the evidence-based starting dose 2.