 |
|
|
|
|
|
 |
 |
 |
 |
 |
 |
 |
 |
  |
 |
|
What is the Safety and Benefit of Kava?
By Andrew Gaeddert, A.H.G. Kava, also known as Kava Kava, has been used for medicinal and ceremonial purposes in the South Pacific for at least two thousand years. It is one of the world's most popular herbs. It is used by up to ninety percent of the population in many Pacific Islands, and is one of the top selling herbs in Europe and the U.S. It is typically used in the west for anxiety, depression and insomnia. Studies have indicated that kava roots contain fiber, proteins, potassium, and compounds known as kavalactones, and as yet unidentified compounds. In European studies, individuals taking kava consistently have shown reduction in feelings of nervousness as well as other symptoms of anxiety such as heart palpitations, chest pains, headache, dizziness, and stomach upset. Unlike benzodiazepines, alcohol and other drugs, kava does not depress mental function. In studies compared with oxazepam (a drug similar to Valium), kava was better tolerated and was shown to improve mental function, in contrast to the drug which was shown to reduce mental function. Recent studies conducted at Duke University shown kava is safe and as effective as prescription drugs for treating stress and anxiety. Drs. Connor, Davidson and Churchill reported, "Kava has several advantages over conventional pharmacological treatments for anxiety - in clinical settings, kava has not been associated with better tolerant capability and lack of physiological dependence and withdrawal." (Natural Foods Merchandiser, New Hope Communications, Boulder, CO. Page 10) Kava was as safe as a placebo by comparing withdrawal symptoms, heart rate, blood pressure and sexual function. The conclusion was that kava could be safely and effectively used to treat anxiety disorders. An analysis of seven clinical trials published in the Journal of Clinical Psychopharmacology supported the beneficial effects of kava to relieve the symptoms of anxiety. No cases of liver toxicity were revealed. This runs contrary to reports of liver toxicity reported in Germany and Switzerland. Approximately 30 cases of liver toxicity have been reported over the last 11 years. The key question is how could an herb that has been safely used for centuries, start showing liver toxicity in a small number of patients? One explanation is the type of extract. European companies frequently use kava stem in the production of their kava products. While having a higher concentration of lactones, kava stem is considered mildly toxic by natives on Fiji. Another explanation is in the preparation of Swiss and German products alcohol and acetone are used to extract constituents, thus producing a much different and more drug like product than what is traditionally used. It is possible that these non-traditional forms of kava yield products that are more toxic to the liver. Natives of the South Pacific consume kava almost exclusively as water extract of the whole root. It is often consumed in group settings after work, where people gather to relax, tell stories and drink kava. In these cultures kava is not consumed with alcohol, and pharmaceutical drug usage is considerably less than in more industrialized countries. This is typically different than the highly individualized western societies where people use kava to help them cope with anxiety, and may be taking a host of other pharmacological substances such as alcohol, anti-anxiety drugs, antidepressants, and other medications, and not getting needed stress reduction, exercise or emotional support to help with their plight. In 18 out of the 30 cases reported in Europe, patients were concurrently taking prescription or over the counter drugs with known or potential liver toxicity along with kava preparations. The remaining cases were people using these potent extracts for long periods of time. To assure consumers and practitioners, The American Herbal Products Association (AHPA) commissioned a toxicology report on kava. All currently available adverse reports were analyzed. According to Donald P. Waller, PhD, a professor of pharmacology and toxicology, "kava, when taken in appropriate dosages for reasonable periods of time, has no scientifically established potential for causing liver damage". Dr. Waller made his conclusions because, after evaluating case reports, it appeared that the adverse reports were due to patients taking kava concurrently with medications with documented liver toxicity, or the cases had inadequate laboratory data. One cannot assume just because a person takes kava that is the cause of the hepatic abnormality. Medications, drug and alcohol use, as well preexisting medical conditions are all vital in establishing a causal relationship. For example, one case report was a woman with Multiple Sclerosis (MS) who was taking kava along with St. John's Wort extract. As there was no information about the patient's drug history, and because her condition usually necessitated medical intervention, one cannot identify kava as the causal agent. In fact, Dr. Waller examined two cases of chronic and high dose consumption of kava that were not associated with liver damage. One case involved an individual consuming four prescription medications plus up to 300 kava pills a day (45,000 mg) without liver damage. Another involved a 13-year old girl who attempted suicide by taking 8-10 500 mg of kava tablets. She was admitted for observation in an intensive care unit, and was discharged the following morning with a complete recovery. According to Dr. Waller, "from a toxicologist's perspective, these two cases provide some evidence that kava itself is not a direct hepatotoxin even in extremely high concentrations." According to the latest statistics, the odds of having kava hepatotoxicity are one in four million. In the drug world this would be considered a favorable risk benefit ratio, however many regulatory and medical authorities have a "zero risk" policy with regards to herbs. Previous to these reports, kava has been observed to cause a scaly skin rash, which typically only occurs with long term heavy usage. Reduction or elimination of kava is the recommended treatment. It is always possible to have an idiosyncratic or hypersensitivity reaction with any food, herb or drug. This appears to be the case in the kava adverse reports. How can kava be used safely and responsibly? First, like all herbs it is best used under the direction and guidance of a health professional knowledgeable about herbs. For example, as a member of the pepper family, kava can be excessively warming and cause conditions described in Chinese medicine as being due to liver heat. These include headache, pressure behind the eyes, hot flashes, and a more dream disturbed sleep. This is why the author uses kava along with the other herbs to heighten beneficial effects while minimizing negative reactions. People who have liver problems or who are taking drugs known to have adverse effects on the liver, including alcohol, should avoid kava. If symptoms of jaundice such as yellowing of the skin and eyes, or dark urine occur, the use of kava should be discontinued. For best results, kava preparations should be thought of as short term adjuncts until the case of the anxiety can be addressed; or through acupuncture, cognitive behavioral therapy or stress reduction techniques the person can improve his or her coping skills. Our current recommendation is not to use kava for more than one to three months without a break. The following are commonly used names for kava:
|
|
| prospective studentscurrent studentsalumnicampusesabout our clinicpacific symposiumnews & eventspublications |
Copyright ©2002-05 Pacific College of
Oriental Medicine. All rights reserved.
|
