What are the effects of administering testosterone to women?

Effects of Testosterone Administration in Women

Testosterone administration in women causes both physical and physiological changes including increased muscle mass, decreased fat mass, deepened voice, increased body and facial hair growth, clitoral growth, increased libido, and potential adverse effects such as polycythemia, reduced HDL cholesterol, androgenic alopecia, and acne. 1

Physical Effects

Testosterone therapy in women produces several masculinizing effects:

• Body composition changes:

  • Increased muscle mass
  • Decreased fat mass 1

• Physical appearance changes:

  • Thicker vocal cords producing deeper voice pitch (irreversible)
  • Increased body and facial hair growth (irreversible)
  • Clitoral growth
  • Androgenic alopecia (hair loss) 1

• Reproductive system effects:

  • Menstrual suppression
  • Increased libido 1
  • Potential gynaecological effects including pelvic pain and genital dryness 1

Adverse Effects and Risks

Testosterone administration in women carries several potential risks:

• Cardiovascular risks:

  • Potentially increased risk of myocardial infarction 1
  • Reduced high-density lipoprotein cholesterol (HDL-c) 1

• Hematological effects:

  • Polycythemia (increased red blood cell count) 1
  • Hemoglobin increases to male reference range within 3 months 1

• Dermatological effects:

  • Acne 1, 2
  • Androgenic alopecia 1

• Virilization concerns:

  • High testosterone doses inevitably cause virilization in women 1
  • Some changes like lowered voice pitch and hair changes are irreversible even if testosterone therapy is discontinued 1

Therapeutic Uses in Women

While not FDA-approved for women 3, testosterone has been used in specific clinical scenarios:

• Hypoactive Sexual Desire Disorder (HSDD):
  • Transdermal testosterone therapy has shown efficacy for HSDD in postmenopausal women 4, 5
  • Benefits include an additional satisfying sexual episode per month and improvements in desire, arousal, orgasm, and pleasure 5
  • Recommended only when HSDD is not primarily related to modifiable factors like relationship or mental health problems 4

Dosing and Administration Considerations

• Dosing:

  • Women have approximately 10-fold lower testosterone levels than men 1
  • Lower doses than those used in men are required to avoid virilization 1
  • Transdermal administration is preferred over oral to minimize lipid profile changes 2

• Monitoring:

  • Total testosterone levels should be monitored to maintain concentrations in the physiologic premenopausal range 4
  • Assessment for signs of androgen excess is necessary 4

Safety Concerns

• Long-term safety data is limited:

  • Short-term studies (up to 2 years) show acceptable safety at physiological levels 2
  • Long-term data on cardiovascular, cancer, and cognitive safety are lacking 5

• Administration methods:

  • Injections or pellets cause supraphysiological testosterone levels and are not recommended 5
  • Compounded products cannot be recommended due to lack of efficacy and safety data 4

Clinical Pitfalls to Avoid

• Using supraphysiologic doses that cause irreversible virilization
• Failing to monitor for polycythemia and lipid changes
• Using injectable or implantable forms that produce unpredictable and often supraphysiologic levels
• Overlooking that some changes (voice deepening, hair growth) are irreversible even after discontinuation
• Using testosterone for indications without sufficient evidence of benefit

The most recent evidence suggests that when used at appropriate doses with proper monitoring, testosterone therapy in women can be relatively safe in the short term, but long-term safety remains uncertain, and the risk-benefit profile must be carefully considered for each clinical scenario.