| Kava (Piper methysticum) has a long history of | | | | reported by 3%. |
| traditional use for the treatment of symptoms | | | | In the United States and Europe, evidence of |
| related to anxiety, stress, nervous restlessness | | | | hepatic failure following the use of kava extracts |
| and has demonstrated effectiveness for | | | | is accumulating. Kava users, experienced liver |
| treatment of anxiety in randomized placebo | | | | failure after consuming kava extract for 2 |
| controlled trials. | | | | months. Liver biopsy revealed active fulminant |
| Kava's popularity were due to the lack of both | | | | hepatitis with extensive necrosis and tests for |
| dependence and documented adverse effects. | | | | viral hepatitis were negative. |
| Kava has been promoted as an axiolytic agent | | | | A 33-year-old woman took 210 mg of kava |
| with little risk for dependence or adverse | | | | extract for 3 weeks and discontinued the product. |
| reactions. An unblinded, comparative, crossover | | | | After 2 months, she resumed taking the same |
| trial of kava (120 mg) and Valerian (600 mg) was | | | | product for an additional 3-week period. |
| conducted, each agent administered for 6 weeks | | | | Symptoms of hepatotoxicity developed a day |
| with a 2 weeks period between. | | | | after ingesting 60 ml of alcohol. Tests for viral |
| This was followed with administration of a | | | | hepatitis were negative and liver biopsy revealed |
| combination of the two compounds. Both stress | | | | evidence of hepatic necrosis. |
| and insomnia were measured regarding social, | | | | According to the US Food and Drug |
| personal, and life Kava 29 events. Results: the | | | | Administration (FDA) advisory letter dated March |
| severity of stress was equally relieved by each | | | | 25, 2002 warned health care providers of a total |
| of the two compounds and there was further | | | | of 11 patients who had used kava products and |
| improvement of insomnia with combination | | | | developed liver failure requiring liver transplantation. |
| therapy. With kava, 67% of the subjects | | | | General consumers should be aware that Kava |
| reported no adverse events, 53% denied adverse | | | | should not be used by anyone who has any liver |
| events with Valerian, and likewise with | | | | problems. In addition, as well as anyone who is |
| combination therapy. Vivid dreams were | | | | taking any drug product with known adverse |
| experienced by 21% of subjects taking | | | | effects on the liver, or anyone who is a regular |
| combination therapy and 16% of those taking | | | | consumer of alcohol. |
| Valerian alone. Dizziness or gastric discomfort was | | | | |