Addictive Potential: None
Emergency Room Visits Yearly: Unkown
Mandatory Minimum Sentence: Unknown
Mechanism of Action: bind to receptors throughout the limbic system
Kava (Piper methysticum) is an ancient crop of the South Pacific. The word kava is used to refer both to the plant and the beverage produced from its roots. The active compounds in Kava are a group of 15 lactones unique to the plant and are collectively known as Kavalactones. There are some alkaloids too, but it is not certain whether any of these are responsible for Kava’s activity.
While the full workings of Kava are still being investigated, it is generally accepted that kavalactones work by binding onto various receptors in the brain particulary the part of the brain known as the amygdala that regulates feelings of fear and anxiety. Research suggests that receptors based in this part of the brain are particularly sensitive to the effects of Kava hence its strong ability to reduce anxiety and promote a feeling of relaxation.
The most significant anti-anxiety studies show that an effective daily dose of kavalactones ranges between 210 – 280 milligrams of kavalactones. To promote sleep, a dose of approximately 140 – 210 milligrams of kavalactones taken thirty to sixty minutes prior to retiring is recommended.
A moderately potent kava drink causes effects within 20–30 minutes that last for about two and a half hours, but can be felt for up to eight hours. Because of this, it is recommended to space out servings about fifteen minutes apart. Some report longer term effects up to two days after ingestion, including mental clarity, patience, and an ease of acceptance. The effects of kava are most often compared to alcohol, or a large dose of diazepam.
The sensations, in order of appearance, are slight tongue and lip numbing (the lips and skin surrounding may appear unusually pale); mildly talkative and sociable behavior; clear thinking; calmness; relaxed muscles; and a sense of well-being. As with drugs that affect the GABA receptors, there can also be paradoxical dysphoria. The numbing of the mouth is caused by the two kavalactones kavain and dihydrokavain which cause the contraction of the blood vessels in these areas acting as a local topical anesthetic. These anesthetics can also make one’s stomach feel numb. Sometimes this feeling has been mistaken for nausea. Some report that caffeine, consumed in moderation in conjunction with kava can significantly increase mental alertness.
A potent drink results in a faster onset with a lack of stimulation; the user’s eyes become sensitive to light, they soon become somnolent and then have deep, dreamless sleep within 30 minutes. Sleep is often restful and there are pronounced periods of sleepiness correlating to the amount and potency of kava consumed. Unlike with alcohol-induced sleep, after wakening the drinker does not experience any mental or physical after effects. However, this sleep has been reported as extremely restful and the user often wakes up more stimulated than he or she normally would (though excessive consumption of exceptionally potent brew has been known to cause pronounced sleepiness into the next day). Although heavy doses can cause deep dreamless sleep, it is reported that many people experience lighter sleep and rather vivid dreams after drinking moderate amounts of kava.
After thousands of years of use by the Polynesians and decades of research in Europe and the U.S., the traditional use of kava root has never been found to have any addictive or permanent adverse effects. Users do not develop a tolerance. While small doses of kava have been shown to slightly improve memory and cognition, large amounts at one time have been shown to cause intoxication. In Utah, California, and Hawaii there have been cases where people were charged with driving under the influence of alcohol after drinking a significant amount of kava (eight cups or more) although some of them were acquitted due to the laws not being broad enough to cover kava consumption.
Side Effects and Adverse Reactions:
Research studies show that Kava does not exhibit any loss of effectiveness over time, and there was no evidence of development of tolerance or resistance to Kava. Thus, there is very little likelihood of addiction at normal doses.
In 2001 concerns were raised about the safety of commercial kava products. There have been allegations of severe liver toxicity, including liver failure in some people who had used dietary supplements containing kava extract (but not in anyone who had drunk kava the traditional way). Out of the 50 people worldwide taking kava pills and extracts that have had some type of problem, almost all of them had been mixing them with alcohol and pills that could have effects on the liver. The fact that different kava strains have slightly different chemical composition made testing for toxicity difficult as well.
The possibility of liver damage consequently prompted action of many regulatory agencies in European countries where the legal precautionary principle so mandated. In the UK, the Medicines for Human Use (Kava-kava) (Prohibition) Order 2002 prohibits the sale, supply or import of most derivative medicinal products. Kava is banned in Switzerland, France, Germany and The Netherlands. The health agency of Canada issued a stop-sale order for kava in 2002. But legislation in 2004 made the legal status of kava uncertain. The United States CDC has released a report expressing reservations about the use of kava and its possibly adverse side effects (specifically severe liver toxicity), as has the Food and Drug Administration (FDA). The Australian Therapeutic Goods Administration has recommended that no more than 250 mg of kavalactones be taken in a 24 hour period. According to the Medicines Control Agency in the U.K., there is no safe dose of kava, as there is no way to predict which individuals would have adverse reactions.
Regular use of Kava may cause a scaly skin disorder resembling psoriasis. This takes four months to a year of regular use to appear, and it is not related to niacin deficiency.
Allergic skin reaction to Kava may manifest after 2 – 3 weeks of regular ingestion of Kava. This reaction can be aggravated by sunlight. The condition is reversible and resolved when Kava intake is stopped.
Kava can also cause pupillary dilatation and lack of skeletal muscle co-ordination. Therefore people taking Kava should not drive or operate heavy machinery.
Kava may also exacerbate depression.
- May potentiate the effect of anxiolytics. Therefore patients on benzodiazepines or other anxiolytics should not take Kava without physician supervision.
- Alcohol and other depressants may potentiate the action of Kava. On the other hand, food decreases the effect of Kava.
- Kava increases renal sodium excretion and may potentiate effects of diuretics.
- Patients on hypoglycemic drugs may need dosage adjustment.
- Phosphatidyl serine