Biest (bi-estrogen) creams combine estradiol (E2) and estriol (E3), often in 50:50 or 80:20 ratios, with micronized progesterone 4% for transdermal menopausal hormone therapy. Estriol is a weaker estrogen thought to favor genitourinary tissue; estradiol provides systemic symptom relief.
Compounded bioidentical HRT is popular in functional medicine but lacks large RCT equivalence to FDA-approved patches. Endometrial protection requires adequate progestogen exposure; unmonitored bleeding warrants evaluation. Salivary hormone testing is not guideline-recommended for dosing.
CLYR Health offers biest + progesterone cream as a women's hormone preview SKU with prescriber-supervised monitoring.