Comparing the effects of estrogen and an herbal medicine on peripheral blood flow in post-menopausal women with hot flashes: Hormone replacement therapy and Gui-Zhi-Fu-Ling-Wan, a Kampo medicine

We investigated the association between blood flow in the extremities and hot flashes, and compared change in blood flow following hormone replacement therapy (HRT) and Gui-zhi-fu-ling-wan (Keishi-bukuryo-gan), a herbal therapy in post-menopausal women with hot flashes. Three hundred and fifty-two post-menopausal women aged 46-58 years (mean: 53.4 +/- 3.6 years) with climacteric complaints participated in the study. One hundred and thirty-one patients with hot flashes were treated with HRT (64 cases) or herbal therapy (67 cases). Blood flow was measured with laser doppler fluxmetry under the jaw, in the middle finger and in the third toe. Post-menopausal women with hot flashes (129 cases) showed significantly higher blood flow under the jaw (13.6 +/- 4.13) than women without hot flashes (166 cases) (5.48 +/- 0.84) (p < 0.0001). Blood flow at this site decreased significantly with either therapy (p < 0.0001). On the other hand, the administration of Gui-zhi-fu-ling-wan significantly increased (p = 0.002) the blood flow in the lower extremities, whereas HRT decreased the blood flow. Thus, we have demonstrated that Gui-zhi-fu-ling-wan did not affect the activity of vasodilator neuropeptides on sensory neurons of systemic peripheral vessels uniformly. Therefore, Gui-zhi-fu-ling-wan, rather than HRT, is suggested as an appropriate therapy for treatment of hot flashes in the face and upper body with concomitant coldness in the lower body, which is one of the symptoms of menopause.