Estriol (E3) is one of the body's natural estrogens. It is used in vaginal creams and gels for dryness and thinning of the vaginal tissue after menopause.
Also known as: E3, estriol cream, oestriol.
We found no estriol product in FDA's Drugs@FDA database, so there are no US label strengths to list. The trials below used a 0.005% vaginal gel, 1 g holding 50 micrograms of estriol (Muiños Fernández 2024). These are study protocols, not a recommendation.
We found no estriol product in FDA's Drugs@FDA database, so estriol has no FDA label to quote. Ask your prescriber about the approved alternatives, such as vaginal estradiol.
What studies show: in 61 women with early breast cancer taking aromatase inhibitors, a 0.005% estriol vaginal gel for 12 weeks improved vaginal tissue, pH, dryness and sexual function scores more than placebo; estriol levels rose at first and were back to normal by week 12, and estradiol and estrone stayed mostly undetectable (Hirschberg 2020). In 108 postmenopausal women with genitourinary syndrome of menopause, the same gel for 24 weeks lowered the rate of urinary tract infections by 26% compared with a plain gel (Muiños Fernández 2024).
These results are for a specific ultra-low-dose vaginal gel and may not apply to other estriol creams, including compounded ones. Estriol is an estrogen; talk to your prescriber about the risks of estrogen use.
We found no published half-life or time to peak for vaginal estriol that we could cite, so we do not list one. In one trial of a 0.005% vaginal gel, blood estriol rose at first and was back to normal by week 12 (Hirschberg 2020).
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