What intramuscular testosterone dose (e.g., testosterone enanthate or testosterone cypionate) is recommended for a menopausal woman experiencing low sexual desire, loss of libido, or mild urogenital atrophy who is already on estrogen therapy?

Testosterone Dosing for Menopausal Women with Low Libido

Testosterone therapy is not FDA-approved for women and should only be considered as a third-line option in postmenopausal women with hypoactive sexual desire disorder (HSDD) who have failed non-hormonal interventions and are already on adequate estrogen therapy.

Absolute Contraindications

Before considering testosterone, you must exclude:

• Active or history of breast cancer or hormone-dependent malignancies 1, 2, 3
• Pregnancy or breastfeeding 2
• Women attempting conception 2
• Cardiovascular disease or liver disease 4

First-Line Treatment Algorithm (Non-Hormonal)

Start here before considering testosterone:

1. Address underlying causes: anxiety, depression, relationship issues, vaginal dryness 3
2. Vaginal moisturizers (3-5 times weekly) plus water-based lubricants during intercourse 3
3. Pelvic floor physical therapy to improve arousal, lubrication, and satisfaction 1, 3
4. Cognitive behavioral therapy for sexual dysfunction 3

Second-Line Pharmacologic Options

If non-hormonal measures fail:

• Flibanserin 100 mg at bedtime daily (FDA-approved for premenopausal HSDD, can be considered off-label for postmenopausal women) 1, 2, 3
• Bremelanotide (FDA-approved for premenopausal women, limited data in postmenopausal) 3
• Bupropion or buspirone (off-label, limited evidence) 1, 2, 3

Expected benefit: approximately 1 additional satisfying sexual event every 2 months 2, 3

Testosterone Therapy (Third-Line Only)

Dosing Regimen

Transdermal testosterone 1% gel, 5 grams applied twice weekly 2

• Apply to dry, intact skin of abdomen, back, upper thighs, or upper arms 2
• Do NOT use testosterone products formulated for men due to excessive dosing risk 4
• Transdermal formulations are strongly preferred over oral due to first-pass hepatic effects 4, 5

Critical Dosing Principle

Women exhibit a bell-shaped dose-response curve for testosterone—exceeding the threshold dose provides no additional benefit and may cause negative effects including aggression and virilization 6. Target mid-range female physiologic levels, NOT male reference ranges (500-600 ng/dL) 2.

Monitoring Protocol

• Baseline: Total and free testosterone, lipid profile, liver function, complete blood count 2
• Every 3 months during first year: Repeat testosterone levels (can be drawn at any time; peak occurs 6-8 hours post-application), lipids, liver enzymes, CBC 2, 4
• Assess efficacy at 3-6 months: If no improvement in sexual desire/satisfaction, discontinue therapy 2, 5
• Maximum treatment duration: 24 months due to lack of long-term safety data 2

Expected Outcomes

• Modest improvement in sexual desire, arousal, and orgasmic response (standardized mean difference ~0.35) 7, 4, 5, 8
• 74% increase in satisfying sexual activity in surgically menopausal women on concomitant estrogen 8
• No proven benefit for: bone density, hot flashes, lean body mass, or general well-being 4

Special Populations

Breast Cancer Survivors

• Systemic testosterone gel is NOT recommended due to unestablished safety 1, 3
• Intravaginal testosterone cream has shown safety and efficacy for vaginal atrophy in breast cancer patients on aromatase inhibitors 3
• Vaginal DHEA should be used with extreme caution in women on aromatase inhibitors, as it increases circulating androgens and may interfere with AI activity 1, 3

Alternative for Vaginal Atrophy (Not Libido)

If the primary complaint is vaginal dryness/dyspareunia rather than low desire:

• Vaginal estrogen (most effective for vaginal symptoms) 1, 3
• Vaginal DHEA (prasterone) (FDA-approved for dyspareunia) 1, 3
• Ospemifene (oral SERM for moderate-to-severe dyspareunia) 1, 3

Common Pitfalls to Avoid

• Never prescribe testosterone without confirming adequate estrogen levels—testosterone may be ineffective without circulating estrogen 2, 4
• Never use testosterone as first-line therapy—exhaust non-hormonal and FDA-approved options first 2, 3
• Never continue beyond 24 months without compelling evidence of sustained benefit and absence of adverse effects 2
• Never target male testosterone ranges—this causes virilization without additional sexual benefit 2, 6
• Never prescribe in women with breast cancer history—safety is not established 1, 2, 3, 4

Side Effects

Most common: application site reactions, hirsutism, acne 4, 8

Unknown long-term risks: breast cancer, cardiovascular disease, thromboembolic events 4, 5