Advancements in nanocarrier-based transdermal estrogen delivery with patents and clinical outcomes

Hormone replacement therapy (HRT) remains the cornerstone for alleviating symptoms associated with menopause by replenishing declining estrogen levels.The primary goal of HRT is to restore estrogen levels, which naturally decline after menopause.The skin provides a convenient and noninvasive route for administering medications, making transdermal drug delivery an area of ongoing research and innovation.Recent advancements have focused on vesicular drug delivery systems such as liposomes, niosomes, and transferosomes, which enhance skin permeability and enable controlled estrogen release.These novel nanocarriers have shown promise in improving the transdermal delivery of drugs with enhancement in skin permeability, offering more accurate dosing and reduced side effects compared to conventional estrogen therapies.This review critically evaluates the transdermal estrogen therapy using nanocarriers, alongside recent patents and clinical trials, to highlight current progress and future directions.