Kavalactones represent the active constituents of kava–kava (Piper methysticum G. Forster), endowed with sedative and anaesthetic properties. Kavalactones are polar constituents, but poorly soluble in water with a low bioavailability. In this study, the formation of inclusion complexes of one of the most represen- tative kavalactone isolated from kava–kava extract, (S)-7,8-dihydrokavain (DHK), with