People in the Pacific Islands, where kava
comes from, have probably used kava for thousands of years. First knowledge of
it in the West came with one of the expeditions led by Captain James Cook in the
1700s. Natives to the islands used kava as part of important rituals and rites,
and it was the focus of many social gatherings. The drink prepared from the
roots numbs the mouth. In the 20th century, kava has been given to many
important visitors to the Pacific Islands. Hillary Rodham Clinton and Pope John
Paul II were given kava during welcoming ceremonies, as were President and Mrs.
Lyndon B. Johnson in 1966.
Kava root can reduce stress-related anxiety
and the effects of anxiety disorders. At lower dosages, kava helps you be more
aware and active, but not tense. At higher dosages, the chemicals in kava root
can make you sleepy. But usually, kava is simply calming, as opposed to the
heavier sedation of alcohol or antianxiety prescription drugs. Health care
providers prescribe kava for pain and stiffness, anxiety, insomnia, menopausal
anxiety, uncontrolled epilepsy, pain, and jet lag.
Plant Description
The root comes from a tall shrub that grows in the islands of the Pacific
Ocean, including Hawaii. This shrub produces large, green, heart-shaped leaves
that grow thickly on the branches, off thick stalks. Long, slender flowers that
look like Chinese baby corn grow where the branches meet the stems. The roots
look like bundles of woody, hairy branches.
What's It Made Of?
Kava root contains chemicals called kavapyrones, which reduce convulsions and
cause muscles to relax in laboratory tests using animals. The kavalactones also
cause reactions in the brain that are believed to be like those caused by
pharmaceutical drugs used for depression and anxiety. Kavalactones are what
numbs your tongue if you put liquid kava in your mouth or on your gums.
Available Forms
In some cultures, kava is prepared by chewing the root and spitting it into a
bowl. The saliva mixes with the root and activates the plant medicine. Today,
manufacturers use alcohol or acetate instead. You can find kava in liquid form,
as tinctures or extracts, and in capsules or tablets. It's also available
powdered or crushed.
How to Take It
If your health care provider has recommended kava, make sure you read the
label to look for kava products that are standardized to contain a 70 percent
kavalactone content. A standardized product is one with a listing of specific
amounts of active plant material per dosage.
For the relief of anxiety and insomnia, and to reduce stress, the recommended
kava dose is 2.0 to 4.0 g as decoction (a preparation made by boiling down the
herb in water) up to three times daily. Take 60 to 600 mg kavalactones daily of
standardized formulas or follow your provider's instructions.
Length of treatment varies. It may take four weeks before you notice
improvement. Recommendations are not to take kava for longer than three months.
Precautions
Kava's side effects are mild. It can numb the mouth and may have an
unpleasant taste. A very small percentage of people report nausea, headache,
dizziness, or skin rash when they take kava. If any of these happen to you, make
sure you tell your health care provider. Don't drive if you are taking Kava.
The American Herbal Products Association (AHPA) advises pregnant and
breast-feeding women not to take kava. It also advises against taking more than
the recommended dosage, using kava for longer than three months at a time, and
driving while using kava.
Missionaries to the Pacific islands during the 19th century
noticed that people who took kava all the
time had yellowish, scaly skin. In a more recent study, people who took 100
times the recommended dose experienced this same yellowing, developed a rash,
lost hair, and had trouble with vision, appetite, and breathing. These changes
go away when you stop taking kava.
Possible Interactions
Do not take kava with alcoholic beverages and medications that have sedative
effects like antihistamines and therapies for anxiety and insomnia. Kava may
increase the effects of these medications.
Kava may reduce the effectiveness of levodopa that is used for the treatment
of Parkinson's disease. Therefore, you should not take this herb if you are
taking any medications containing levodopa.
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