Up to 80% of women experience hot flashes during perimenopause — lasting on average 7–10 years, not months. They are not vague hormonal inconveniences. They are neurological events driven by KNDy neurons in the hypothalamus misfiring when estrogen declines. In 2025, the FDA approved elinzanetant — the first drug to target this exact brain pathway — reducing hot flash frequency by 74%. HRT risk warnings were also revised. The treatment landscape just changed. Here's the full s