kava Kava Benefits and Side Effects

KAVA KAVA
[PIPER METHYSTICUM] benefits and side effects

Kava is a perennial shrub native to some islands of the South Pacific and has been cultivated
for centuries to prepare a psychoactive beverage from its rhizoma by means of extraction.

KAVA KAVA [PIPER METHYSTICUM]

According a few online retailers, most users of kava kava report a state
of relaxation, peacefulness, mild euphoria and initial alertness (followed
by drowsiness) after taking kava kava. Kava is known as a muscle
relaxant and a local anesthetic; it numbs the tongue and throat when you
drink it as a liquid extract. Occasionally drinkers may experience mild side
effects such as double vision. Excessive drinking of kava may lead to
skin issues and loss of appetite.

After reading their advertisements, I have a few questions: What is kava
kava? Is it a psychotic drug or something similar to LSD? Does it cause
dependence to the users? Anyway, I continue to read their articles.

Then, the online retailers will further expand it in their websites: Kava
kava refers to both the plant (Piper methysticum) and the drink made
from it. Piper methysticum is a shrub belonging to the pepper family
Piperaceae. First, people ground the kava root into a brownish powder.
They then mix the powder with water and drink it as a beverage. While,
supplement manufacturers may just place the kava root extracts in
capsules and sell the capsules as kava capsules.

A typical commercial kava tablet contains 750 mg of kava kava whole
lateral root. They use dicalcium phosphate as diluent, microcrystalline
cellulose as tablet binder, gum acacia as disintegrant, magnesium
stearate as lubricant and silicon dioxide as anti-sticking agent. The
average assay is about 97.5 mg of kavalactones (or 13%). They
recommended 1-2 kava capsule(s) a day and do not take more than 3-4
days a week. In addition, there should be a week off each month for
dosing. Kava extract liquid is also available in the market.

Kava kava contains kawain, methysticin, and yangonin, and they are
known as kavalactones or pyrones. There are two types of extracts:
water-soluble extract and fat soluble extract. It seems that the fat-soluble
extract have more pharmacological activities as it can kill pain and induce
drowsiness, while the water-soluble extract can kill pain only.
Manufacturers claim that Kava is even superior to aspirin.

RESEARCH FINDINGS

ANTI-ANXIETY
Clinical studies have shown that kava and kavalactones are effective in
the treatment of anxiety at sub-clinical and clinical levels, anxiety
associated with menopause and anxiety due to various medical
conditions. [4]

ANTI-CANCER
Researchers have identified flavokawain A, B, and C but not the major
kavalactone, kawain, in kava extracts as strong antiproliferative and
apoptotic agents for human bladder cancer cells. [5]

SLEEP IMPROVEMENT
A significant shortening of the sleep latency in sleep-disturbed rats was
observed following the administration of kava-kava extract at a dose of
300 mg/kg. Delta activity was also significantly increased during
non-REM sleep in sleep-disturbed rats. [6]

CHEERFUL MOOD
In a double-blind randomized placebo-controlled trial using healthy
subjects, the intake of a single dose of Kava extract (300 mg; p.o.) led to
an increase in state cheerfulness. The mood-elevating effects of Kava
were most prominent in trait cheerful subjects, indicating that trait
cheerfulness moderated the drug-induced increase in cheerful mood. [7]

COGNITIVE PERFORMANCE
In a double-blind randomized placebo-controlled trial using healthy
subjects, kava improved the accuracy and the speed of performing the
partial report and the item recognition task, indicative of a beneficial
effect of the phytopharmacon on visual attention and short-term memory
retrieval, respectively. [7]

KAVA SIDE EFFECTS
Short-term usage of Kava may be safe. The adverse effects attributed to
kava use are considered mild or negligible, except for the occurrence of
a skin lesion. [4] However, a major concern was raised in accordance
with emerging reports that relate Kava use to major hepatic damage,
including a few cases of fulminant hepatitis that required liver
transplantation or ended in death. [1]. Three possible mechanisms for
kavalactone hepatotoxicity are suggested: inhibition of cytochrome P450,
reduction in liver glutathione content and, more remotely, inhibition of
cyclooxygenase enzyme activity. [3]

Consumption of kava is dangerous for patients in the perioperative
period. Kava may cause direct decreases in systemic vascular resistance
and blood pressure. Kava inhibits cyclooxygenase to potentially cause a
decrease in renal blood flow and to interfere with platelet aggregation.
Kava may also potentiate benzodiazepine and induction anesthetic
potency and cause excessive perioperative sedation. [2]

References:
[1] Ben-Arye E et al, Weighing the efficacy and safety of herbal medicine: the case of
Kava-Kava, Harefuah. 2004 Aug;143(8):592-7, 621. [2] Raduege KM et al, Anesthetic
considerations of the herbal, kava.J Clin Anesth. 2004 Jun; 16(14):305-11. [3]
Clouatre DL Kava kava: examining new reports of toxicity. Toxicol Lett. 2004 Apr
15;150(1):85-96. [4] Singh YN et al, Therapeutic potential of kava in the treatment of
anxiety disorders. CNS Drugs. 2002;16(11):731-43. [5] Zi X et al, Flavokawain A, a
novel chalcone from kava extract, induces apoptosis in bladder cancer cells by
involvement of Bax protein-dependent and mitochondria-dependent apoptotic
pathway and suppresses tumor growth in mice. Cancer Res. 2005 Apr
15;65(8):3479-86. [6] Shinomiya K et al, Effects of kava-kava extract on the
sleep-wake cycle in sleep-disturbed rats. Psychopharmacology (Berl). 2005
Jul;180(3):564-9. Epub 2005 Feb 8. [7] Thompson R et al, Enhanced cognitive
performance and cheerful mood by standardized extracts of Piper methysticum
(Kava-kava). Hum Psychopharmacol. 2004 Jun;19(4):243-50.

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BEFORE TAKING ANY SUPPLEMENTS OR IF YOU HAVE ANY QUESTIONS.

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