Remifemin does not stop hot flashes, but does help me significantly with the problem of being hot and sweaty at all times during perimenopause. Because I feel drier, I can tolerate hot weather better and when I do have a hot flash, I cool off faster (and if it occurs at night, my sleep is only temporarily interrupted). It does take about 4 weeks to notice this effect. I took it during most of a whole year and decided to try stopping it when I ran out this fall. After about 3 weeks, I started Remifemin again. I could not do without it.