The roots of the plant are used to produce a drink with sedative and anesthetic properties. Kava is consumed throughout the Pacific Ocean cultures of Polynesia, including Hawaii, Vanuatu, Melanesia and some parts of Micronesia. Kava is sedating and is primarily consumed to relax without disrupting mental clarity.
Kava is chewed by some to relieve symptoms of throat pain, as it produces a “numbing” effect on the tongue and throat. Kava has been reported to improve cognitive performance and promote a cheerful mood.
Info found on Wikipedia.