- Although scientific studies provide some evidence that kava may be beneficial for the management of anxiety, the U.S. Food and Drug Administration (FDA) has issued a warning that using kava supplements has been linked to a risk of severe liver damage.<a href="#hdng0">(More...)</a>
<a name="hdng0"></a>
Although scientific studies provide some evidence that kava may be beneficial for the management of anxiety, the U.S. Food and Drug Administration (FDA) has issued a warning that using kava supplements has been linked to a risk of severe liver damage. <a href="
http://nccam.nih.gov/health/kava/" TARGET="_blank"
[1]</a> Tell your health care providers about any herb or dietary supplement A product that contains vitamins, minerals, herbs or other botanicals, amino acids, enzymes, and/or other ingredients intended to supplement the diet. The U.S. Food and Drug Administration has special labeling requirements for dietary supplements and treats them as foods, not drugs. you are using, including kava. This helps to ensure safe and coordinated care.<a href="
http://nccam.nih.gov/health/kava/" TARGET="_blank"
[1]</a>
Avoid driving and operating heavy machinery while taking kava because the herb has been reported to cause drowsiness.<a href="
http://nccam.nih.gov/health/kava/" TARGET="_blank"
[1]</a> Kava has been reported to cause liver damage, including hepatitis and liver failure (which can cause death).<a href="
http://nccam.nih.gov/health/kava/" TARGET="_blank"
[1]</a>
Kava is not a proven therapy for other uses. NCCAM-funded studies on kava were suspended after the FDA issued its warning.<a href="
http://nccam.nih.gov/health/kava/" TARGET="_blank"
[1]</a> Kava may interact with several drugs, including drugs used for Parkinson's disease.<a href="
http://nccam.nih.gov/health/kava/" TARGET="_blank"
[1]</a> Today, kava is used primarily for anxiety, insomnia, and menopausal symptoms.<a href="
http://nccam.nih.gov/health/kava/" TARGET="_blank"
[1]</a> The root and rhizome (underground stem) of kava are used to prepare beverages, extracts, capsules, tablets, and topical solutions.<a href="
http://nccam.nih.gov/health/kava/" TARGET="_blank"
[1]</a> Kava has also been used to help people fall asleep and fight fatigue, as well as to treat asthma and urinary tract infections.<a href="
http://nccam.nih.gov/health/kava/" TARGET="_blank"
[1]</a> Kava has been used as a ceremonial beverage in the South Pacific for centuries.<a href="
http://nccam.nih.gov/health/kava/" TARGET="_blank"
[1]</a>
Kava has been associated with several cases of dystonia (abnormal muscle spasm or involuntary muscle movements).<a href="
http://nccam.nih.gov/health/kava/" TARGET="_blank"
[1]</a>
Recent reports from health authorities in Germany, Switzerland, France, Canada, and the United Kingdom have linked kava use to at least 25 cases of liver toxicity, including hepatitis, cirrhosis, and liver failure. Although liver damage appears to be rare, the FDA believes consumers should be informed of this potential risk.<a href="
http://nccam.nih.gov/health/alerts/kava/" TARGET="_blank"
[2]</a> The U.S. Food and Drug Administration (FDA) is advising consumers of the potential risk of severe liver injury from the use of dietary supplements containing kava (also known as kava kava or Piper methysticum ).<a href="
http://nccam.nih.gov/health/alerts/kava/" TARGET="_blank"
[2]</a>
Products containing kava are sold in the United States for a variety of uses, including insomnia and short-term reduction of stress and anxiety. These products are marketed to men, women, children, and the elderly.<a href="
http://nccam.nih.gov/health/alerts/kava/" TARGET="_blank"
[2]</a>
Safety is a concern for users of kava. People, especially those with liver disease or liver problems, or persons who are taking drugs that can affect the liver, should talk with their health care practitioner before using kava.<a href="
http://nccam.nih.gov/health/alerts/kava/" TARGET="_blank"
[2]</a> Until recently, kava was generally thought to be safe: when used in otherwise healthy people not taking any other drugs, herbs, or supplements; over short periods of time (one to two months); and at recommended doses.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Based on multiple human reports of liver toxicity, including hepatitis, cirrhosis, and liver failure, a theoretical increased risk of liver damage may occur if kava is taken with drugs that may injure the liver such as alcohol or acetaminophen (Tylenol®).<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> There is concern regarding the potential danger from taking kava based on multiple reports from Europe and the United States that included hepatitis, cirrhosis, and liver failure.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a>
Multiple cases of liver damage have been reported in Europe, including hepatitis, cirrhosis, and liver failure. Kava has been removed from shelves in several countries due to these safety concerns.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Multiple cases of liver toxicity, including liver failure, have been reported following the use of kava in Europe.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> The U.S. Food and Drug Administration (FDA) has issued warnings to consumers and physicians and has requested that physicians report cases of liver toxicity that may be related to kava use.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> The U.S. Food and Drug Administration (FDA) has issued warnings to consumers and physicians. It is not clear what dose or duration of use is correlated with the risk of liver damage. The quality of these case reports has been variable; several are vague, describe use of products that do not actually list kava as an ingredient, or include patients who also ingest large quantities of alcohol.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Letter to health-care professionals: FDA issues consumer advisory that kava products may be associated with severe liver injury.<a href="
http://www.cdc.gov/MMWR/preview/mmwrhtml/mm5147a1.htm" TARGET="_blank"
[4]</a>
Since 1999, health-care professionals in Germany, Switzerland, and the United States have reported the occurrence of severe hepatic toxicity possibly associated with the consumption of products containing kava (i.e., kava kava or Piper methysticum ).<a href="
http://www.cdc.gov/MMWR/preview/mmwrhtml/mm5147a1.htm" TARGET="_blank"
[4]</a> Humbertston C, Akhtar J, Krenzelok E. Acute hepatitis induced by kava kava, an herbal product derived from Piper methysticum.<a href="
http://www.cdc.gov/MMWR/preview/mmwrhtml/mm5147a1.htm" TARGET="_blank"
[4]</a> Escher M, Desmeules J, Giostra E, et al. Hepatitis associated with kava, a herbal remedy for anxiety.<a href="
http://www.cdc.gov/MMWR/preview/mmwrhtml/mm5147a1.htm" TARGET="_blank"
[4]</a>
In May 2001, a previously healthy woman aged 45 years reported the onset of nausea and weakness approximately 8 weeks after beginning use of a kava-containing dietary supplement that listed on the package label, "Kava kava extract (root), standardized to 30% kavalactones (75 mg), hops (strobiles), German chamomile (flower head), passion flower (flower and fruit), gelatin, and natural vegetable fiber."<a href="
http://www.cdc.gov/MMWR/preview/mmwrhtml/mm5147a1.htm" TARGET="_blank"
[4]</a> Kava is a botanical product derived from the rhizome and roots of Piper methysticum, a shrub indigenous to the South Pacific.<a href="
http://www.cdc.gov/MMWR/preview/mmwrhtml/mm5147a1.htm" TARGET="_blank"
[4]</a> Seven patients used kava prepared either by ethanol or acetone extraction methods; one patient used an unspecified type of kava-containing product.<a href="
http://www.cdc.gov/MMWR/preview/mmwrhtml/mm5147a1.htm" TARGET="_blank"
[4]</a> Kava-containing products might differ based on the absolute amount of kava pyrones present and on the relative distribution of kava pyrones.<a href="
http://www.cdc.gov/MMWR/preview/mmwrhtml/mm5147a1.htm" TARGET="_blank"
[4]</a> FDA will continue to investigate the relationship, if any, between the use of dietary supplements containing kava and liver injury.<a href="
http://www.cfsan.fda.gov/~dms/addskava.html" TARGET="_blank"
[5]</a>
The presence of kava in a supplement should be identified on the product label in the "Supplement Facts" box.<a href="
http://www.cfsan.fda.gov/~dms/addskava.html" TARGET="_blank"
[5]</a> Kava ( Piper methysticum ) is a plant indigenous to the islands in the South Pacific where it is commonly used to prepare a traditional beverage.<a href="
http://www.cfsan.fda.gov/~dms/addskava.html" TARGET="_blank"
[5]</a> The agency's investigation includes attempting to determine a biological explanation for the relationship and to identify the different sources of kava in the U.S. and Europe.<a href="
http://www.cfsan.fda.gov/~dms/addskava.html" TARGET="_blank"
[5]</a>
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Section Contents:- A case of muscle cell breakdown (rhabdomyolysis) was reported in a 29 year-old man after taking an herbal combination of ginkgo, guarana, and kava.<a href="#hdng1">(More...)</a>
- Serious hepatic adverse effects include hepatitis, cirrhosis, and liver failure.<a href="#hdng2">(More...)</a>
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A case of muscle cell breakdown (rhabdomyolysis) was reported in a 29 year-old man after taking an herbal combination of ginkgo, guarana, and kava. Sedation (drowsiness) has occasionally been reported with kava use, although there is early evidence from several small human studies that kava may not significantly cause this effect. Because this issue remains unclear, driving and operating heavy machinery is not recommend while taking kava. <a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Several cases of abnormal muscle movements have been reported after short-term use of kava (one to four days), including tightening, twisting, or locking of the muscles of the mouth, neck (torticollis), and eyes (oculogyric crisis).<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Chronic or heavy use of kava has also been associated with cases of neurotoxicity, pulmonary hypertension, and dermatologic changes.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Eye disturbances and eye irritation have rarely been associated with chronic or heavy kava use.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Kava may interact with herbs and supplements with anti-cancer or hormonal activity; use cautiously.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Caution is advised while driving or operating machinery. In theory, kava may add to the effects of herbs and supplements that act like monoamine oxidase inhibitor (MAO-I) drugs, such as evening primrose oil. It may also add to the effects of herbs that have activity similar to the class of antidepressants known as selective serotonin reuptake inhibitors (SSRIs).<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Since kava has diuretic properties, it may have additive effects when taken with diuretic herbs or supplements like horsetail or licorice.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> People using other herbs or supplements that may increase the risk of bleeding should speak with a healthcare professional before starting kava.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Preliminary evidence shows that kava may interfere with the way the body processes certain herbs or supplements using the liver's "cytochrome P450" enzyme system.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a>
There have been numerous reports of severe liver problems in people using kava.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Natural Standard has collaborated with the World Health Organization (WHO) to prepare a detailed report of kava and associated adverse effects, which is now available.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Early evidence shows that kava may interfere with the way the body processes certain drugs using the liver's "cytochrome P450" enzyme system. The levels of these drugs may be altered in the blood, which may cause different effects or potentially serious adverse reactions.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Avoid in Parkinson's disease or in patients with a history of medication-induced extrapyramidal effects because kava may cause additive effects. Kava may cause excessive drowsiness when taken with SSRI antidepressant drugs such as fluoxetine or sertraline.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> In theory, kava may increase the effects of alcohol or other drugs that cause sedation (drowsiness). In theory, kava may interfere with the effects of dopamine or drugs that are similar to dopamine and may worsen the neurologic side effects of drugs that block dopamine such as haloperidol (Haldol®).<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Kava may have additive sedative effects when taken concomitantly with the opioid analgesics oxycodone and propoxyphene. Kava may also interact with anti-cancer drugs or hormonal drugs, such as birth control pills.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> There may be decreases in the muscle strength of the uterus with the use of kava, which may have harmful effects on pregnancy. Chemicals in kava may pass into breast milk with unknown effects, and therefore this herb should be avoided during breastfeeding.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Currie BJ, Clough AR. Kava hepatotoxicity with Western herbal products: does it occur with traditional kava use? Med J Aust 2003;178(9):421-2.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a>
Human studies have found at least moderate benefit of kava in the treatment of anxiety, and early evidence suggests that kava may be as effective as benzodiazepine drugs such as diazepam (Valium®).<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Stevinson C, Huntley A, Ernst E. A systematic review of the safety of kava extract in the treatment of anxiety.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Pittler MH, Ernst E. Efficacy of kava extract for treating anxiety: systematic review and meta-analysis.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a>
Garrett KM, Basmadjian G, Khan IA, et al. Extracts of kava (Piper methysticum) induce acute anxiolytic-like behavioral changes in mice.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Ulbricht C, Basch E, Boon H, et al. Safety review of kava (Piper methysticum) by the Natural Standard Research Collaboration.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a>
Consult with a qualified healthcare professional before taking kava due to the risk of harmful side effects.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Laboratory tests suggest that kava may increase the risk of bleeding through effects on blood platelets.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Agents broken down by the kidneys should be used cautiously with kava due to increased risk of kidney damage.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Kava beverages, made from dried roots of the shrub Piper methysticum, have been used ceremonially and socially in the South Pacific for hundreds of years and in Europe since the 1700s.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Kava may have chemical properties similar to monoamine oxidase inhibitors (MAO-I). In theory, kava may add to the effects of MAO-I antidepressants, such as isocarboxazid (Marplan®), phenelzine (Nardil®), or tranylcypromine (Parnate®). Due to this possible effect, kava may also cause the effects of anesthesia to last longer and some practitioners recommend stopping kava two to three weeks before surgery.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Kava has been shown to increase 'off' periods in Parkinson's patients taking levodopa and can cause a semicomatose state when given with alprazolam.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a>
Worsening of symptoms of Parkinson's disease and several cases of abnormal whole body movements (choreoathetosis) following high doses of kava have also been noted. Tremor, poor coordination, headache, drowsiness, and fatigue have uncommonly been reported, particularly with large doses.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Doses as high as 800 milligrams daily of kava extract have been taken for short periods, but have not been studied over the long term and safety is not clear.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> A dose of 100 milligrams of kava extract (WS 1490) has been taken three times daily.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Typical doses range from 50 to 280 milligrams of kava lactones per day at bedtime.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Many experts believe that kava is neither sedating nor tolerance-forming in recommended doses.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a>
There is not enough scientific evidence to recommend the use of kava in children.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> There is growing concern regarding the potential for liver toxicity from kava.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Kava may affect electroconvulsive therapy (ECT) outcome. It has also been associated with meningismus (pain caused by irritation in the layers around the brain and spinal cord), urinary retention, skin lesions, enhanced or decreased cognitive performance, anorexia, sleeplessness, abnormal sensations called paresthesias, vomiting, and dangerously high blood pressure.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Connor KM, Payne V, Davidson JR. Kava in generalized anxiety disorder: three placebo-controlled trials.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Rapid heart rate, electrocardiogram (ECG) abnormalities, and shortness of breath have been reported in heavy kava users.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Early study results suggest that kava and valerian may be beneficial to health by reducing the body's reactions during stressful situations and stress induced insomnia. Further research is needed to confirm these results.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a>
Kava's effects were reported to be similar to the prescription drug buspirone (Buspar®) used for Generalized Anxiety Disorder (GAD) in one study.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a> Several well-conducted human studies have demonstrated kava's efficacy in the treatment of anxiety with effects observed after as few as one to two doses and progressive improvements over one to four weeks.<a href="
http://www.nlm.nih.gov/medlineplus/druginfo/natural/patient-kava.html" TARGET="_blank"
[3]</a>
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<a name="hdng2"></a>
Serious hepatic adverse effects include hepatitis, cirrhosis, and liver failure. At least one patient required a liver transplant. Based on their assessment of the adverse events reported to them, the regulatory authority in Switzerland has prohibited the sale of products containing the kava extract associated with the adverse effects. <a href="
http://www.fda.gov/MedWatch/SAFETY/2001/kava.htm" TARGET="_blank"
[6]</a> Products containing herbal extracts of kava have been implicated in cases of serious liver toxicity in Germany and Switzerland. Approximately 25 reports of hepatic toxicity associated with the use of products containing kava extracts have been reported in these countries.<a href="
http://www.fda.gov/MedWatch/SAFETY/2001/kava.htm" TARGET="_blank"
[6]</a> The agency is investigating whether the use of dietary supplements containing kava (also known as kava kava or Piper methysticum) is associated with liver toxicity.<a href="
http://www.fda.gov/MedWatch/SAFETY/2001/kava.htm" TARGET="_blank"
[6]</a> Dietary supplements containing kava are promoted for a variety of uses, including relaxation (e.g., to relieve stress, anxiety, and tension), insomnia, and postmenstrual syndrome (PMS).<a href="
http://www.fda.gov/MedWatch/SAFETY/2001/kava.htm" TARGET="_blank"
[6]</a>
Last month, the German authorities issued a proposal to remove all kava extract-containing products from the market.<a href="
http://www.fda.gov/MedWatch/SAFETY/2001/kava.htm" TARGET="_blank"
[6]</a>
Kava kava may increase the effect of alcohol and of certain drugs used to treat anxiety and depression.<a href="
http://www.cancer.gov/dictionary/?searchTxt=kava" TARGET="_blank"
[7]</a> The U.S. Food and Drug Administration advises users that kava kava may cause severe liver damage.<a href="
http://www.cancer.gov/dictionary/?searchTxt=kava" TARGET="_blank"
[7]</a>
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