Herbs for the nervous system: Ginkgo, kava, valerian, passionflower

The World Health Organization estimates that 80% of the world’s population relies on herbal medicine, with the use of herbs in the United States expanding significantly in the past decade. Alternative and herbal medicines—such as St. John’s wort, kava, ginkgo biloba, and valerian, among others—have become increasingly popular treatments for nervous and sleep disorders including stress, anxiety, dementia, and forgetfulness. This article reviews the use of ginkgo, kava, passionflower, and valerian in psychiatric practice, summarizing existing research on these major botanicals. Herbal remedies are compared with pharmaceuticals, and dosages, benefits, adverse effects, and drug–herb interactions are discussed for each herb.