What are the treatment options for decreased libido in postmenopausal women?

Treatment Options for Decreased Libido in Postmenopausal Women

For postmenopausal women with decreased libido, begin with nonhormonal pharmacologic options as first-line therapy, specifically low-dose SSRIs (avoiding paroxetine if on tamoxifen), SNRIs, or gabapentin/pregabalin, while addressing vaginal atrophy with local estrogen therapy; flibanserin can be considered as it shows efficacy in postmenopausal women, though testosterone remains an off-label option with demonstrated efficacy but limited long-term safety data. 1, 2, 3, 4

First-Line Nonhormonal Pharmacologic Options

Antidepressants are the preferred initial treatment for decreased libido in postmenopausal women. 1

SSRIs and SNRIs

• Low-dose paroxetine (7.5 mg daily) reduces vasomotor symptoms and improves sexual function, though doses for libido are much lower than those needed for depression 1
• Critical caveat: Pure SSRIs, particularly paroxetine, should be avoided in women taking tamoxifen due to CYP2D6 inhibition blocking tamoxifen's conversion to active metabolites 1
• SNRIs provide an alternative with similar efficacy and faster response times than traditional antidepressant dosing 1
• Common side effects include dry mouth, decreased appetite, fatigue, nausea, constipation, and potential sexual dysfunction 1

Anticonvulsants

• Gabapentin and pregabalin improve menopause-related symptoms including sexual dysfunction 1
• These agents work through neuropathic pain pathways and can address multiple menopausal complaints simultaneously 1

Addressing Vaginal Atrophy

Vaginal dryness affects approximately 50% of postmenopausal women and directly contributes to decreased libido through dyspareunia. 1, 5

Local Estrogen Therapy

• Vaginal estrogen is useful for concomitant vaginal atrophy and dyspareunia, which are major contributors to decreased libido 3
• Unlike systemic estrogen, vaginal estrogen specifically targets local symptoms without significant systemic absorption 3
• Ospemifene (a selective estrogen receptor modulator) serves as an alternative to vaginal estrogen 3
• Important distinction: Systemic estrogen therapy is not recommended in the absence of vasomotor symptoms and is not directly associated with desire 3

Clinical Impact

• 78% of perimenopausal and 87% of postmenopausal women believe vaginal dryness is a factor causing reduced libido 5
• Aromatase inhibitors cause significantly more vaginal dryness (18%) compared to tamoxifen (8%), making local estrogen therapy particularly important in breast cancer survivors 1

FDA-Approved Medication: Flibanserin

Flibanserin demonstrates efficacy in postmenopausal women with hypoactive sexual desire disorder (HSDD), though it was originally approved only for premenopausal women. 2, 6, 4

Efficacy Data

• The PLUMERIA trial showed flibanserin (100 mg daily at bedtime) significantly improved FSFI desire domain scores in postmenopausal women (P = 0.011) 4
• Results in approximately 1 additional satisfying sexual event every 2 months compared to placebo 2, 6
• The mechanism of action remains unclear but involves central nervous system neurotransmitter modulation 2

Safety Profile

• Most common adverse events are insomnia (7.7%), somnolence (6.9%), and dizziness (6.4%) 4
• Generally well tolerated in naturally postmenopausal women 4

Critical Limitation

• Flibanserin has NOT been evaluated in women with a history of cancer or those on endocrine therapy, and the risk/benefit ratio in these populations remains uncertain 2

Off-Label Option: Testosterone

Exogenous testosterone has demonstrated efficacy in treating loss of desire in postmenopausal women, but it is not FDA-approved for this indication and lacks long-term safety data. 3

Clinical Evidence

• Testosterone shows benefit in some postmenopausal women (23 of 50 women in one survey found it useful) 5
• Patients with iatrogenic premature ovarian insufficiency may suffer from diminished libido due to low circulating testosterone levels 1
• Progestins with anti-androgenic effects should be avoided in women with hypoandrogenism as they can worsen libido 1

Counseling Requirements

• Patients must be informed that testosterone is not FDA-approved for decreased libido 3
• Limited published long-term safety data exists 3
• Bupropion (an antidepressant with some androgenic properties) has shown improvement in desire in some women with and without depression 3

Assessment and Monitoring

Initial Evaluation

• Laboratory evaluation should include estradiol, FSH, LH, and prolactin as clinically indicated 1
• Important caveat: FSH is not a reliable marker of menopausal status in women with prior chemotherapy, pelvic radiation, or those on tamoxifen 1
• Pelvic evaluation should assess for vaginal atrophy 1

Multifactorial Contributors

• Sexual dysfunction in postmenopausal women involves complex interplay of body image changes, psychosocial trauma, relationship quality, and hormonal factors 1
• At least 50% of women after breast cancer experience sexual dysfunction including decreased libido 1
• Direct questioning is necessary as many women will not volunteer this information 5, 7

Special Populations

Breast Cancer Survivors

• Nonhormonal options are strongly preferred as first-line therapy 1
• Chemotherapy and endocrine therapy commonly induce ovarian dysfunction and severe menopausal symptoms 1
• Women on aromatase inhibitors experience more severe vaginal atrophy than those on tamoxifen 1

Women with Bilateral Oophorectomy

• Over 90% experience hot flashes and other menopausal symptoms that may be particularly severe and long-lasting 1
• These women commonly experience significant atrophic vaginitis 1