Hi'iaka's Healing Herb Garden

Is Kava Safe?

News reports about herb safety might have left you confused and perhaps fearful about the possible harmful side effects of herbs such as kava kava (Piper methysticum; known as ‘awa in Hawai‘i). These reports have stated that kava can be toxic to your liver and that it can interact with prescription medications. But what’s the truth?

Kava is well known as a relaxing, pain-reducing beverage: it’s the best-researched herb for promoting relaxation and reducing feelings of anxiety. The active ingredients are a group of chemical compounds called kavalactones, which have a depressant effect, so it’s useful for insomnia, fatigue and nervousness. It also relaxes tense muscles and helps relieve chronic pain because of its diuretic and analgesic effects.

The traditional Polynesian way of taking kava is to dry the root, grind it, and mix it with room temperature water. Kava drinkers believe this method is safe and can document no cases of people developing liver disease as a result of long-term use. They also believe that kava should not be mixed with hot water or any sweeteners or fruit, but I have not been able to find any evidence that mixing kava with fruit sugars is harmful. A common caution about kava is that you shouldn’t mix it with alcoholic beverages: take tinctures and elixirs made with brandy or vodka only as directed (in small doses). Kava also is available in capsule form. Follow label directions and don’t take more than the recommended dosage.

The press has reported that 28 people in Europe suffered liver damage after consuming kava. HerbalGram magazine reported in March 2007: “During the past few years, pharmaceutical and dietary supplement products made from kava have been banned from sale in many countries based on the suspicion of severe hepatic adverse effects.” According to Mark Blumenthal of the American Botanical Council (ABC, which publishes HerbalGram), “in three of the cases other potentially hepatotoxic (toxic to the liver) drugs had been taken and concurrent viral infections and alcohol use could not be ruled out.... In many cases, detailed information on the patients’ history, co-medication, consumption of alcohol and further particulars are missing, thus not permitting a sound evaluation of these cases.” Blumenthal concludes, “Expert analysis of case reports says there is insufficient evidence to make causal connection. Despite a large number of pharmacological and toxicological studies, and even new clinical trials published since the ban, no convincing proof of an inherent toxicity of kava exists.”

As with many other pleasurable parts of life, we should take kava and other herbs in moderation. Always follow label instructions if you're taking any herbal pill or tincture. If you enjoy a cup or two of kava tea at the farmers market, continue to do so. But think twice before you drink many cups of the stuff every day.

In 2002, the ABC suggested the following cautions:

“Kava should not be used by anyone who has any liver problems, or by anyone who is taking any drug products with known adverse effects on the liver, or anyone who is a regular consumer of alcohol.

“Since the reports so far are associated with chronic use, kava should not be taken on a daily basis for more than four weeks (without the advice of a qualified professional).

“Discontinue use if symptoms of jaundice (e.g., dark urine, yellowing of the eyes) occur.

“Consult your primary health care provider if you have a history of liver problems or suspect possible liver problems before using kava or continuing its use.”

Herb-drug interactions can occur, so if you're taking any prescription tranquilizers (brand names such as alprazolam and diazepam or valium), other sedatives such as sleeping pills, anesthetics or analgesics, don’t take kava. Combining drugs of this type with kava might interfere with your mental or motor functions because the herb can magnify the drugs’ effects.

Use caution if you take any herbs with prescription medicines: St. John's wort, ginkgo, valerian, ephedra, garlic, licorice, ginseng, senna, and cascara sagrada are associated with possible interaction problems. Many herb magazines are in publication and there are tons of Web sites devoted to herbs, so get in the habit of reading about herbs in order to inform yourself about their safety and better yet, their miraculous healing effects and uses.

On the Web:
herbalgram.org, issue 73
herbsforhealth.com