Lady's slipper (Cypripedium acaule, Cypripedium calceolus)

Background

Lady's slipper is a wildflower in the orchid family (Orchidaceae). Yellow lady's slipper (Cypripedium calceolus), named American valerian after Indian valerian (Valeriana wallichii), which comes from India, shares similar medical properties with pink lady's slipper. Once commonly used to treat various nervous disorders, it is a mild stimulant and is antispasmodic. Lady's slipper has been described in the folklore as a stimulant and a sedative, and no reports are currently available to confirm these opposite proposed actions. It is also often used to treat depression related to female problems. Having been almost wiped out by collectors for such medical use, it is now too rare to be used medically.
Pink lady's slipper (Cypripedium acaule) was considered a substitute for the preferred yellow lady's slipper as a medicinal plant. Used as a sedative and antispasmodic, it was substituted for the European valerian. It has also been used for male and female disorders.
Presently, there are no high quality human clinical trials available evaluating the safety and efficacy of lady's slipper. However, traditional users and some herbal experts suggest that more research may be warranted to investigate the antispasmodic and sedative/stimulant actions of lady's slipper.

Liu D, Ju JH, Zou ZJ, et al. Isolation and structure determination of cypritibetquinone A and B, two new phenanthraquinones from Cypripedium tibeticum. Yao Xue.Xue.Bao. 2005;40(3):255-257.
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Schmalle H, Hausen BM. A new sensitizing quinone from lady slipper (Cypripedium calceolus). Naturwissenschaften 1979;66(10):527-528.
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