In an otherwise healthy 48-year-old female patient, acute hepatitis with transaminase increase (GOT up to 613 U/l, GPT up to 752 U/l), inconspicuous hepatitis serology findings, negative autoantibody status and negative virus serology was observed after a 10-week long intake of kava-kava (1-3 x 200 mg/day) and St John's Wort (1 x 425 mg/day). Biopsy of the liver showed lobular and portal necroinflammatory activity without indication of cirrhosis.