​This clinical factsheet provides an overview of kava and its associated health risks, referral options for drug and alcohol counselling services, and where to go for further advice.

Last updated: 05 December 2022
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About kava

Kava (also known as kava kava or Piper methysticum) is a member of the pepper plant family, which contains the psychoactive ingredient kavalactones and acts as a central nervous system depressant.
 
Kava is widely consumed in Pacific and South Sea Island communities where the root of the kava plant is usually ground or chewed up and mixed with water or coconut milk to form a traditional beverage. As a ceremonial drink, kava has been used for formal occasions, such as weddings, festivals, and family functions. It is also consumed as a social and recreational beverage.
 
Kava is also used for medicinal and therapeutic purposes for the relief of stress, anxiety, and insomnia.
 
The safety profile of kava is mostly based on traditional use and descriptive studies, and as such, there is an absence of robust clinical evidence concerning kava’s impacts on human health.
Recent changes to importation laws have made kava more widely available in Australia, increasing the potential for kava use outside the traditional practice and population.

Dosage

There is no well-established toxic dose for kava.
 
Reported dosage of kavalactones from traditional kava use varies substantially, ranging from 750 to 8,000 mg of kavalactones per day.
 
Most capsule formulations range from 50 to 100 mg, with a recommended maximum daily dose of 250 mg.

Effect

Kavalactones are known to have a dose-dependent depressant effect on the central nervous system. After ingestion it generally takes 1.8 to 3.0 hours
to reach peak serum (blood) levels, with a half-life of 9 hours.
 
Short-term effects: muscle relaxation, drowsiness, and feelings of well-being.
 
Intoxication effects: sedation, muscle weakness, reduced coordination, fatigue, and hepatotoxicity.
High doses: paralysis of extremities, involuntary movement, deafness, dilated pupils, deep sleep.
 
Long-term effects: dermopathy, weight loss, gastrointestinal disturbance, red eyes, impotence, poor overall health, and fatigue.

Potenital harms

Minors

Young people may experience greater psychoactive effects of kava than adults due to lower body weight. Kava use by young people is not recommended.

Pregnant and breastfeeding women

There is limited evidence on the safety of kava use during pregnancy and breastfeeding. Kava use is not recommended in this group. Some studies have shown that kava is transmitted in breastmilk.

Kava and driving impairment

Kava use (depending on the amount consumed) may affect perceptions, alertness, and responsiveness and therefore a person’s ability to drive safely. Data from some countries, in which drivers who had consumed kava before driving and then became involved in a motor vehicle collision, suggest that kava has the potential to impair driving ability. Consumption of kava before driving a motor vehicle or operating machinery is not recommended. If feeling affected by kava avoid driving and using machinery.

Addiction/Dependence 

Evidence suggests that kava is not addictive. However, harmful use of kava, including ongoing, high-level consumption, has been known to occur in certain contexts.

Interactions with other substances 

Kava is known to have similar pharmacological mechanisms to other drugs and medications, raising the risk of adverse interactions between kava and
other drugs.

Kava may potentiate the effects of other central nervous system depressants such as benzodiazepines, barbiturates, or alcohol. There is evidence that consuming kava and alcohol at the same time can cause intoxication, increased drowsiness, impaired reflexes, and increased risk
of liver damage.

Some research has shown that kava may affect the metabolism of certain drugs and may increase or decrease their effects in an unpredictable manner. Interactions of kava with levodopa (used to treat Parkinson’s disease), caffeine, anticonvulsants, monoamine oxidase inhibitors (MAOIs),
antipsychotics, antiplatelet medications, or anticoagulants have been postulated. Further clinical studies are required to understand possible
adverse effects.

Referral to drug and alcohol counselling services

For 24-hour drug and alcohol support, information, counselling, and referral to services in NSW call the Alcohol and Drug Information Service (ADIS)
on 1800 250 015.

Further advice

Poisons Information Centre is a 24/7 call centre serviced by specialists in poisons information and clinical toxicologists across Australia. Call 13 11 26.

Drug and Alcohol Specialist Advisory Service (DASAS) is a free 24/7 telephone service that provides general advice to health professionals who require assistance with the clinical diagnosis and management of patients with alcohol and other drug related concerns.

Contact DASAS:

Within Sydney Metropolitan Area: (02) 8382 1006. Regional, Rural & Remote NSW: 1800 023 687

Current as at: Monday 5 December 2022
Contact page owner: Centre for Alcohol and Other Drugs