Kava is a tropical evergreen shrub with large heart-shaped leaves and woody stems. Its thick roots are mashed or ground and made into a cold beverage used similarly to alcohol. It has a long history of ritual and recreational use in Pacific Polynesia and is now a common herbal product.
The roots of the plant are used to produce a drink with sedative, anesthetic, and entheogenic properties. Kava is consumed throughout the Pacific Ocean cultures of Polynesia, including Hawaii, Vanuatu, Melanesia and some parts of Micronesia. (See canoe plants.) Kava is sedating and is primarily consumed to relax without disrupting mental clarity. Its active ingredients are called kavalactones. A Cochrane Collaboration systematic review of its evidence concluded it was likely to be more effective than placebo at treating short-term social anxiety.