Kava Kava is a traditional herbal medicine that can be used to treat anxiety and depression through its interaction with dopamine, serotonin and GABA neuroreceptors (Grunze et al 2001).

For centuries, mankind have always opted natural products as an important companion in aiding illnesses and health-related diseases [1]. Kava kava is a member of the pepper family, and has been used as a ceremonial drink in the pacific Islands for all sorts of celebrations and social rituals. Kava kava was also seen as a way to connect with the spiritual world. 

Traditionally the rhizomes were chewed or ground into a pulp mixed with cold water to create a thick brew that would slightly numb the mouth and produce feelings of well being, tranquility, and contentment. The use of this plant in medicinal practices has been dated back to the eighteenth century [4].

When Capitan Cook made his first voyage into the pacific in the 1760s he and his crew encountered kava for the first time and went on to introduce the herb to Europe.

A number of literatures have reported a variety of therapeutic properties in this plant species, such as anti-inflammatory, anti-cancer and anti-oxidant properties [4, 5, 6].

As an herbal medicine kava became very popular for treating anxiety, insomnia and related nervous disorders and as an effective alternative to prescription tranquillisers and antidepressants

 

  1. Depression 

Depression affects an estimated 400,000 people in Ireland and 300 million around the world. Antidepressants prescribed are usually synthetic drugs and these can sometimes cause a wide range of unpleasant side effects. Kava has been shown to possess mild anti depressant properties, making it suitable for the treatment of anxiety associated with depression – without the negative side effects of prescribed anti depressants (Sarris et al 2009). 

https://www.ncbi.nlm.nih.gov/pubmed/19430766

 

2. Insomnia

Its also a hypnotic and so a useful treatment for insomnia. Kava helps to improve the quality of sleep significantly. It reduces active wakefulness and significantly prolongs sleep, compared with placebo. Unlike prescription drugs for anxiety, kava does not appear to interfere with mental alertness, up set the stomach, or foster a dependency on the herb (Yurcheshen et al 2015)

https://www.ncbi.nlm.nih.gov/pubmed/26265921

Wheatley 2001

https://www.ncbi.nlm.nih.gov/pubmed/11536390

 

3. Anti anxiety effects  

A major scientific review of kava concluded that kava extract has significant anti anxiety activity and is superior to placebo for treating anxiety 

(Pittler & Ernst 2000). 

https://www.ncbi.nlm.nih.gov/pubmed/10653213

According to the authors of the review, none of the trials reported any hepatotoxic events and seven trials measured liver enzyme levels as safety parameters and reported no clinically significant changes. The herb appears to be as effective treating anxiety as popular prescription tranquillisers such as diazepam.

 

4. Benzodiazepine withdrawal 

Kava may have a role in reducing anxiety and improving subjective wellbeing during benzodiazepine withdrawal, according to a 2001 randomised, double-blind, placebo-controlled study 

Malsch & Kieser 2001

https://www.ncbi.nlm.nih.gov/pubmed/11605083

 

5. Analgesic and local anaesthetic (pain)

Kava has been found to have analgesic and local anaesthetic effects. The constituent kavain acts as a pain killer. The effect is not mediated by an opiate pathway

Korman et al 2012

https://www.ncbi.nlm.nih.gov/pubmed/23406752

 

6. Antispasmodic 

Kava also acts as an antispasmodic. Because its an effective muscle relaxant, it is an appropriate treatment for conditions associated with muscle spasm, neck tension and headaches,

Mills & Bone 2000 Herbs and Natural Supplements Vol 2

 

7. Menopasual and perimenopasual anxiety 

In a review of the commonly used botanicals for treatment of mood and anxiety disorders in perimenopausal and postmenopausal women kava was found to hold promise for decreasing anxiety in peri- and postmenopausal women

Geller and Studie 2007 

https://www.ncbi.nlm.nih.gov/pubmed/17194961

 

8. Cancer 

Kava kava has been reported to possess anticancer and anti-inflammatory activities. We are well aware that the state of the immune system and the inflammatory process that can develop both play vital roles in the progression of cancer.

A study in the South Pacific where cancer rates are low, despite high rates of tobacco consumption – found that the more kava consumed by a population the lower the cancer incidence for a population – the data suggests there is a close inverse relationship between cancer incidence and kava consumption 

Steiner 2000

https://www.ncbi.nlm.nih.gov/pubmed/11149250

Other studies have shown kava to have anti cancer properties 

Nadiah Abu et al 2013

https://cancerci.biomedcentral.com/articles/10.1186/1475-2867-13-102

Kava has also been found to protect agains prostate cancer

Li X et al 2015 

https://www.ncbi.nlm.nih.gov/pubmed/26497688

and breast cancer 

Abu N et al 2015

https://www.ncbi.nlm.nih.gov/pubmed/26179368

 

9. Anti-inflammatory activity

Kava also acts an an anti inflammatory and so helps to protect and fight against disease 

The anti-inflammation activity of flavokawain A was examined by Kwon et al. in 2013 [23]. 

 

10. Boosts Immune System

Kava boosts the immune system and so protects against illness and disease 

https://www.ncbi.nlm.nih.gov/pubmed/26411010

 

Preparation and dose 

Recommended dosage for kava depends upon the concentration of kavalactones. 

Commission E recommends preparations equivalent to 60 to 120 mg kavalactones taken three times a day.

 

Caution 

Use of kava is not recommended for pregnant or breastfeeding women.

Long term use can lead to a yellow discolouration of the skin, hair, and nails, this is a temporary condition known as ‘kava dermopathy’ and reverses once discontinued 

Finally, anyone with liver problems should not use kava. 

Kava causes relaxation and drowsiness, and therefore kava should never be used when driving or operating machinery.

Kava’s safety is still being studied and debated. 

However over the past few years, concerns about possible liver toxicity resulting from the use of kava have grown, based on several reports of liver damage, including hepatitis, cirrhosis, and liver failure in Europe.  

The second general problem identified has to do with those taking kava. The chance of getting liver problems was six times higher when people took other medicines or herbal remedies at the same time. 

Alcohol intake might also increase the risk of toxicity, but the evidence here is not as clear cut.

Also, four out of every five people who experienced adverse effects were taking higher doses for longer periods than traditionally recommended.

The United States Food and Drug Administration and similar regulatory bodies in other countries have issued warnings to consumers and physicians. 

However a recent ban on kava in Germany has been rescinded. 

The World Health Organisation investigated the issues, and its report contributed to many bans being lifted.

Many Western countries have lifted their bans and introduced strict import and sales regulations. However, a range of different products remains available.

 

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