DHEA for Vaginal Dryness

DHEA placed in the vagina helps vaginal dryness a little; DHEA swallowed as a supplement has not been shown to help at all. In the largest placebo-controlled trial, 325 postmenopausal women used a 6.5 mg vaginal DHEA insert (prasterone) every night for 12 weeks. Among the 84% with moderate to severe dryness, it improved by 1.44 severity units from baseline, but only 0.27 units more than with placebo (P = 0.004) (Labrie 2016). A 2026 meta-analysis of five trials in 1,611 women found a similar small benefit (mean difference -0.23) (Lemos 2026).

A systematic review for the US Agency for Healthcare Research and Quality rated that benefit as low certainty, and concluded that systemic DHEA, the kind sold as a pill, may provide no benefit for menopausal vaginal symptoms (Danan 2024). So the verdict here is mixed: a modest, real effect for a prescription vaginal product, and nothing for the supplement form.

DHEA is an inactive precursor hormone. The trial investigators propose that vaginal DHEA acts through local androgen and estrogen formation, with cells in the vaginal wall converting it into active hormones on the spot (Labrie 2009); the FDA label says the mechanism is not fully established (FDA label). In the phase III trial, parabasal cells (immature cells typical of a thin, atrophic lining) fell by 27.7% more than with placebo, superficial cells rose by 8.44% and vaginal pH dropped by 0.66 units (all P < 0.0001), while blood steroid levels stayed within normal postmenopausal values (Labrie 2016).

That local action is not perfectly contained. In cancer survivors, vaginal DHEA raised blood DHEA-S and testosterone in a dose-dependent way, and 6.5 mg a day raised estradiol, though levels stayed in the lowest half or quartile of the postmenopausal range (Barton 2018b).

Oral DHEA raises hormone levels throughout the body rather than delivering them to the vaginal wall. A higher blood level doesn't mean the vaginal tissue benefits: the federal review found systemic DHEA may provide no benefit for genitourinary symptoms of menopause (Danan 2024). The proposed mechanism may explain why the vaginal insert works; it can't be borrowed to justify capsules.

Every positive trial used DHEA inside the vagina. The approved product is a 6.5 mg prasterone insert placed once a day at bedtime with an applicator; in the US it is a prescription medicine indicated for moderate to severe pain during sex caused by menopause (FDA label). The 0.50% (6.5 mg) dose is the one tested in the phase III trials, and lower and higher strengths (0.25% and 1.0%) worked similarly in the earlier dose-finding trial (Labrie 2009).

Daily use matters. When women switched from daily use to twice a week after 2 weeks, the benefit for dryness faded and was no longer significant at 12 weeks (P = 0.198) (Bouchard 2015). No oral DHEA dose has been shown to ease vaginal dryness, so there is no supplement dose to recommend.

Vaginal DHEA isn't the first step for everyone. The North American Menopause Society says non-prescription moisturisers and lubricants give enough relief for most women with mild symptoms, and lists low-dose vaginal estrogen, vaginal DHEA, systemic estrogen and ospemifene as effective for moderate to severe symptoms (NAMS 2020).

In the first phase III trial, 216 postmenopausal women with vaginal atrophy used vaginal DHEA at one of three strengths or a placebo every day for 12 weeks. At the 0.5% strength, the severity of their most bothersome symptom fell by 1.5 score units, and vaginal cells and pH improved (all P < 0.0001 vs placebo), with changes visible from 2 weeks (Labrie 2009).

The confirmatory trial analysed 482 women whose main symptom was painful sex. With 6.5 mg nightly, pain during sex fell 0.36 units more than with placebo (P = 0.0002), and moderate to severe dryness, present in 84% of the women, fell 0.27 units more (P = 0.004) (Labrie 2016). Combining three such trials (436 women on prasterone, 260 on placebo), dryness improved by 0.31 units over placebo (P < 0.0001) (Labrie 2017).

The 2026 meta-analysis pooled five randomised trials (1,611 women): vaginal DHEA improved dryness by a mean difference of -0.23 (95% CI -0.35 to -0.11) and painful sex by -0.40 (95% CI -0.66 to -0.15), with mild, infrequent side effects (Lemos 2026). Set against the 1.44-unit improvement from baseline in the largest trial, most of which also happened on placebo, that is a small extra step (Labrie 2016).

The federal review of 46 trials of menopausal vaginal treatments judged that vaginal DHEA may improve dryness, painful sex and symptom bother, but rated the certainty low, noted most studies lasted 12 weeks or less, and found few long-term or head-to-head data (Danan 2024). Most of the placebo-controlled trials were run by the developer's research group, so independent replication is thin.

A three-arm trial run by a US cancer research network randomised 464 postmenopausal women with a history of breast or gynaecological cancer to vaginal DHEA 3.25 mg, 6.5 mg or a plain moisturiser for 12 weeks. Every group improved, and neither DHEA dose beat the moisturiser for dryness or painful sex at 12 weeks (6.5 mg P = 0.08; 3.25 mg P = 0.48). The 6.5 mg dose was ahead at 8 weeks (P = 0.005) and improved overall sexual function scores (P < 0.001) (Barton 2018a).

Because there was no inert placebo arm, the trial can't say how much of the improvement came from the moisturiser itself, but it does show DHEA's extra benefit over a moisturiser for dryness is small at best.

No randomised trial has shown that DHEA capsules ease vaginal dryness. The federal review concluded systemic DHEA may provide no benefit for these symptoms (Danan 2024). In the Cochrane review of 28 trials in 1,273 menopausal women, oral DHEA showed no clear effect on sexual function (SMD 0.11, 95% CI -0.13 to 0.35; 5 trials, 340 women), while the single vaginal DHEA trial did (SMD 0.42), although the review found the difference between routes was not statistically significant (Scheffers 2015). For the wider picture, see DHEA for menopause and DHEA for low libido.

Vaginal DHEA was well tolerated in trials. Vaginal discharge from the melting insert was the only side effect the phase III investigators linked to treatment, in about 6% of women over 12 weeks (Labrie 2016). The FDA label reports vaginal discharge in 5.7% of women on the insert versus 3.7% on placebo in 12-week trials, and in 14.2% of women in a 52-week trial, which also recorded abnormal Pap smears in 2.1% (FDA label). Endometrial biopsies from 668 women, some treated for 52 weeks, showed no stimulation of the womb lining (Portman 2015), but the North American Menopause Society notes endometrial safety hasn't been studied beyond a year (NAMS 2020). In an uncontrolled pilot of 10 breast cancer survivors on aromatase inhibitors, blood estradiol stayed low over 6 months (3.4 to 4.3 pg/ml) (Mension 2022).

Across DHEA trials in menopausal women, all routes combined, DHEA raised the odds of androgenic side effects, mainly acne (odds ratio 3.77; 5 trials, 376 women) (Scheffers 2015). Vaginal DHEA is labelled only for women after menopause; its safety in pregnancy and breastfeeding is unknown (FDA label).

Vaginal DHEA raises blood DHEA-S and testosterone a little, and at 6.5 mg a day it raised estradiol in women not taking aromatase inhibitors (Barton 2018b). Those small systemic effects are why hormone-sensitive cancer treatment and other hormone therapies deserve a conversation before you start.