An herbal supplement for PMS and stress management. Key Benefits Helps relieve symptoms of PMS. Has calming properties. May help promote restful sleep. Tang Kuei (or dong quai) is a Chinese herb traditionally used to support the female reproductive system.* Tang Kuei Plus includes tang kuei root, with chamomile for premenstrual and menstrual challenges.* Usage Use with Herbalife's Xtra-Cal® to further promote women's health.