Kava Kava is a best-seller based on its proven ability to relieve stress, anxiety and tension. In late 2001, kava came under the scrutiny of the FDA, which is acting on reports from Europe that kava may damage the liver. Based on these reports, the U.K. has banned sales of kava products and German authorities have notified manufacturers of kava products that their licenses to market the herb could be withdrawn.
Closer examination of the scant details available on the 30 European cases reveals that the vast majority - 21 cases in all - involved the concurrent use of hepatotoxic drugs and/or alcohol. This is not significant evidence of hepatotoxicity.
The fact is, you are far likelier to suffer from liver damage by taking the prescription anti-anxiety drug, Valium, than you are from kava, yet it is taken by millions daily with little question and with no major adverse publicity. The over-the-counter pain medication, acetominphen (Tylenol), also has a high incidence of liver toxicity, especially when combined with alcohol.
Kava is usually sold in a standardized form for which the total dose of kavalactones per pill is listed. The dose used should supply about 40-70mg of kavalactones tid. The total daily dosage should not exceed 300mg of kavalactones. Be patient, because the benefits may take a while to develop. As a sleep aid, the recommended dose is 75-100mg of kavalactones; for a stronger sleep-inducing effect, take 150-210mg on an empty stomach, before bed.
The American Herbal Products Association offers the following advice:
Do NOT use Kava if you have liver disease or a history of liver problems or alcoholism; currently take medications or regularly consume alcohol; are under age 18; or are pregnant or lactating. Kava extracts inhibit the activities of liver detoxifying enzymes increasing the suspicion that kava may cause significant drug interactions. [Drug Metab Dispos 2002;30(11): pp.1153-7]
Continuous use of Kava should be limited to 4 weeks and daily consumption of Kava should NOT exceed 300mg of kava lactones daily.
Use of Kava should be discontinued and medical advice obtained if symptoms, such as nausea, fever, dark urine, yellowing of eyes and skin, occur.