Piper methysticum G. Forst

Kava-kava, the extract of Piper methysticum G. Forst., has been used as a euphoriant and sedative for centuries in several South Paciflc islands. Several lactones are the purported active ingredients, although their precise pharmacologic role remains undefined. Adverse reactions have been associated with heavy use of kava, but the effects of intermittent use are unknown. ... 

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