Kava for stress and anxiety, side effects, safety, risks, toxicity and effect on liver - Benefit, dosage, and research information along with a review of safety, toxicity, and potential risk if misused, Kava capsules and liquid supplements for sale
July 26 2017 by
Ray Sahelian, M.D.

Kava is the term used for both the root plant and the beverage made from it. The beverage is prepared from the root of a shrub called the pepper plant, Piper methysticum, found in Polynesia, Melanesia, and Micronesia, including the islands of Vanuatu, Fiji, and Tonga. The kava root is ground to a powder, and it has a brownish color. The brownish powder is then mixed with water and drank as a beverage, without being fermented. Extracts from the root are placed in capsules and sold as supplements. I don't recommend the use of kava in children or by teenagers. This stress reducing herb should only be used by healthy adults, and only occasionally.

Additional herbs and nutrients involved in relaxation, stress relief and anxiety reductions include passion flower extract, tryptophan, 5-HTP, ashwagandha, lemon balm, theanine, GABA amino acid, and valerian herb.

Natural sleep products with natural herbs and nutrients can help you sleep better
If you are planning to use a kava supplement for sleep or relaxation at night, consider natural sleep inducing products with theanine, passionflower, 5-HTP, melatonin, and other sleep inducing nutrients.

How will kava make you feel, what you may notice when you take the pills
Not everyone reacts exactly the same way to this herb. This is due to the fact that each one of us has a different biochemistry. Furthermore, different products on the market have different amounts of constituents within them, depending on the time of year of the harvest, which island it's from, how's its processed, etc. The form of kava, whether liquid, tincture, or capsule, may also make a difference on how you feel, or how quickly you feel the effects. However, most of the time, the effects are noticed within an hour or two.

As a rule, the following are some common feelings that most users report after taking kava either as a capsule or in liquid form:

     A state of relaxation, without feeling drugged
     Muscle tenseness is less
     Peacefulness and contentment
     More sociable, especially with the right company
     Mild euphoria, sometimes
     Mental alertness is often not effected, except on high doses
     Initial alertness followed by drowsiness which comes on after a few hours, so kava can be taken in the evening, a few hours before bedtime.

Warning: Stop and see a doctor if you develop symptoms that may signal liver problems (e.g., unexplained fatigue, abdominal pain, loss of appetite, fever, vomiting, dark urine, pale stools, yellow eyes or skin). Not for use by pregnant or breastfeeding women. Excessive use, or use with products that cause drowsiness, may impair your ability to operate a vehicle or heavy equipment. Take frequent breaks from use. Short term side effect with high doses include disorientation and ataxia (loss of balance while walking).

Q. I'm reading your book on Kava from the 1990s. It's a bit old, but I wonder if you still feel the same way about using it? I believe the book mentions that it could block dopamine receptors? So, if someone were to use it regularly whether for one month or six months, would it cause your brain dopamine levels to drop?
   A. I think this plant has a role to play in medicine in terms of relaxation and offering some anxiety relief but I do not think it should be taken more than twice a week. At this level of use I would not expect it to cause any harm to the body or mind.

What's in kava root?
As with any herbal medicine, a number of compounds contribute to its medical effects. The active compounds are concentrated in the root of the plant. Kava contains a variety of chemicals known as pyrones or kavalactones. Specific names of the six major kavalactones include
kawain, dihydrokawain, methysticin, dihydromethysticin, yangonin, and desmethoxyyangonin.
   The water-soluble extract contains different compounds than the fat-soluble extract. The central nervous activity of the water-soluble extract was determined in mice to have mild pain-killing ability, but did not induce sleep. The fat-soluble extract had sleep inducing and marked pain-killing properties. The pharmacological effects appear to be due to the activity of the compounds present in the fat-soluble fraction.
   Many of the studies used a standardized extract, called WS 1490, from a German manufacturer. The kava products you find over the counter are likely to contain the active ingredients. Kavalactones are not measured in routine drug tests.  I'm not sure exactly what the half-life of kavalactones are, but the clinical effects, i.e., what a person will notice, only last a few hours.

I just bought a bottle of 30 capsules of kava from GNC. On the back of the GNC bottle it says per serving 250 mg of kava root extract 4:1. What is that mean?
    It should also say on the bottle what percent kavalactones it contains. For instance, it has 250 mg of kava root extract, and most products are about 30 percent kavalactones (the active constituents), hence you would be getting about 75 mg of kavalactones. A range between 50 and 100 mg per pill is usually adequate to help induce relaxation.

Use for anxiety and tension relief
Australian researchers tested the effects of a particular water-soluble kava extract currently sold in that country. Some supplements are alcohol-based extracts that contain plant parts not used in traditional kava preparations. The water-soluble, or "aqueous," extract used in the current study was derived from the peeled rootstock of a medicinal cultivar of kava. Jerome Sarris, a doctoral candidate at the University of Queensland, asked 60 adults with chronic anxiety symptoms to take either the kava pills or placebo pills for one week. During the second treatment week, placebo patients were switched to kava and kava patients to placebo.
Patients' anxiety symptoms declined on the kava extract, as did depression symptoms in some. There were no signs of liver toxicity or other serious side effects, according to Jerome Sarris. Psychopharmacology, 2009. Warwick, Australia-based MediHerb Pty Ltd supplied the kava extract.

Kava-Kava extract LI 150 is as effective as Opipramol and Buspirone in Generalised Anxiety Disorder--an 8-week randomized, double-blind multi-centre clinical trial in 129 out-patients.
Phytomedicine. 2003.
Patients received either 400 mg Kava LI 150, 10 mg Buspirone or 100 mg Opipramol daily for 8 weeks. The product was well tolerated and as effective as Buspirone and Opipramol in the acute treatment of out-patients suffering from GAD.

Kava treatment in patients with anxiety.
Phytother Res. 2004 Apr.
The goal of this placebo-controlled double-blind outpatient trial was to obtain more information on the dosage range and efficacy of a kava special extract WS 1490 in patients with non-psychotic anxiety. 50 patients were treated with a daily dose of 3 x 50 mg kava extract during a 4-week treatment period followed by a 2-week safety observation phase. In the active treatment group, the total score of the Hamilton anxiety scale (primary efficacy variable), showed a therapeutically relevant reduction in anxiety versus placebo. Kava extract WS 1490 was well tolerated and showed a safety profile with no drug-related adverse events or post-study withdrawal symptoms.

Most everyone who uses kava does not find it to be addictive. However, there may be rare individuals who have have a tendency to overuse it.

Beta blockers
I have been prescribed beta blockers to take during a flight, as I suffer panic attacks during these. Can I also take kava at the same time to reduce my anxiety. I do get very anxious before flying.
   As long as the dosages are kept low, and you have no medical problems or taking other medicines, the combination should be okay. Propranolol, a beta blocker should be limited to 40 mg when combined with 70 mg of kavalactones. Also, get approval from your private physician before using this combination.

Birth control pills
I am not aware of any studies that indicate it reduces the effectiveness of birth control pills.

Children and adolescents
Why is it not recommended that children and teenagers use this product?
    Since there is a very small chance that kava could be harmful to the liver in some adults when used regularly, it is possible the same could occur in children. Since there is little research done with this root in children or teenagers, we don't know if their liver is more, or less, sensitive to its effects. Therefore caution is advised.

Diabetics may use this herb only occasionally since no studies have been done on its safety in those who have diabetes.

I was wondering if it is safe to take kava while pregnant. I was taking one capsule daily prior to my pregnancy. Once I found out I was pregnant I stopped taking it.
   The safety of kava has not been evaluated thoroughly in pregnant humans and to be on the safe side, it would be best not to take it although you may consider consulting with your obgyn doctor regarding the occasional use of this herb such as a few times a month in case the anxiety is severe enough to otherwise necessitate the use of pharmaceutical medicines.

Public speaking
I am someone who has a very difficult time with giving oral presentations. I was wondering if kava would help me if I were to take a pill on the day I am supposed to give a presentation? Would this perhaps lower my fear? 
   Kava may help you relax, but it could also make your mind not as sharp. In my experience a small dose of 20 to 40 mg of the pharmaceutical medicine propranolol works better.

After years of insomnia and bad side effects from Buspar I have been enjoying an increased quality of life beyond belief on the kava herb, occasional use helps me sleep at night but not always.
   Kava does not induce sleep consistently and you may have to, with trial and error, find the best time to take it in the evening. Some people sleep better taking kava in the early evening, while others do better taking it an hour or two before bed. It also depends on the product.

I have been taking kava for anxiety for about 2 months. I have also been taking a sleep aid that contains 5 htp, choline, valerian, and melatonin. I have recently learned that I am going to have gallbladder surgery. Is there any chance of any of these nutrients reacting with the anesthesia and if so, how long will they stay in my system? I also take a long list of other nutrients including coq10 and vinpocetine.
   These nutrients should be out of your system within a few days. So, just stop taking them a few days or better yet a week before surgery.

Withdrawal symptoms
There does not appear to be any significant withdrawal symptoms that I am aware of.

Kava side effects, adverse events, risk, safety and danger
Tiredness and decreased sex drive or sensation are some kava side effects that have been reported with frequent use. In the Pacific islands, daily consumption of kava kava liquid for several years or decades leads to a skin condition. A kava side effect from daily use is lowered sex drive. If you have a lowered libido from kava use, or for other reasons, consider Passion Rx.

Sexual side effect, reduced libido
I have been taking four 200 mg tablets of kava complex per day for a few months now and have noticed a diminished sex drive and erections that either are not full at the start or diminish after a short time. This is not the normal situation for me. I am sixty five and in good health.

My boyfriend is 43 years old and been drinking kava tea and taking pills to reduce anxiety. He is now experiencing problems ejaculating. Previously he was on Celexa and experienced the same problem.

Just want to add that my libido has been all but eliminated since taking kava. Might be a good herbal for prison inmates. I do not find this reduced need to be a problem as it can be a wonderful relief to be free of a very strong sex drive for awhile. Many of my male friends have mentioned that sometimes they wish they could get a break form nature's desire to make more of itself at their almost constant expense, it's a kind of serenity.

About a couple of years back, I took kava almost every day, about 60 mg/day for 6 months. I took it to cope with anxiety related premature ejaculation. I have not taken it in the last year but I have also noticed a drastic drop in libido, and a recent visit to the endocrinologist and a hormone assay revealed secondary hypogonadism. Could a long term use of high doses caused my pituitary to shut down?
   It is unlikely that kava shuts down the pituitary gland (this hasn't yet been reported in the medical literature) but little is known about the long term effects of this, and many other herbs and supplements. Hence, cycling (i.e. taking breaks) is important. It is possible though, that kava can anesthetize nerves and reduce sexual sensation, but this would be temporary. The use of sexual enhancing herbs could potentially reverse this process.

I've been taking kava on and off for a three years at higher than average doses. Originally I started using it in capsule form, and then moved to a milled product that was mixed with warm water and literally caused me to vomit. Later I prepared my own brew with raw kava powder, but kept most of the pulp aside - the traditional method. Well, about a year ago I noticed my face getting really red the day after ingesting kava. I took a year or so off, and recently brewed some more. The next morning I noticed the same reaction - and analyzed my symptoms more closely: a very red face, including scalp, ears, throat and neck. The redness felt warm and was most significant on the facial area of the nose and cheeks, but actually extended on to my upper chest (collar bone area) upper central back, and a bit of an itchy feeling on the chest area.  I came across this information recently : The long-term use has reportedly lead to "kawanism", which is characterized by dry, flaking, discolored skin; reddened eyes; a scaly skin rash; puffy face; muscle weakness; blood abnormalities; and feelings of poor health.
    We are familiar with a skin reaction that occurs in the Pacific islands in people who drink kava daily for many years. However, since your kava reaction occurred even after a year of absence on repeat exposure, it is difficult to say why it happened, perhaps an allergic reaction did occur. It's an interesting case history.

Driving caution, also do not use with alcohol
Do not drive a vehicle or operate heavy machinery if you have ingested a high dose of kava or have drank many cups of the juice or drank more than a couple of ounces of wine with it. A small glass of wine or a little amount of alcohol should be fine, as long as you are staying at home and not driving and not making this a regular habit. There is a possible increase in car crashes

PLoS One. 2016. Driving following Kava Use and Road Traffic Injuries: A Population-Based Case-Control Study in Fiji. In this study conducted in a setting where recreational kava consumption is common, driving following the use of kava was associated with a significant excess of serious-injury involved road crashes.

Liver harm and potential toxicity
There have been reports of individuals in Europe with liver damage while consuming kava on a regular basis. A few reports of liver damage in the US have also been mentioned. There are many individuals in the Pacific islands who consume kava on a regular basis for almost a lifetime with no apparent liver damage reported. Drinking it has been part of their culture for hundreds of years. Kava, traditionally consumed in the Pacific as juice or water extracts, has been found to contain far less kavalactones than what is present in capsules.
   It is possible that liver damage in some individuals is due to kava. However, it is possible in others that it it not the culprit, or the only culprit. Some of those with liver damage were taking other medicines along with the kava, or were very old. Maybe some of them abused alcohol or had a history of hepatitis. It is also possible that the extraction method to make kava capsules in Europe is different than that in the US which explains more cases reported in Europe than in the states. Europeans extract the kavalactones by hexane or acetone, and make their product contain 70% kavalactones while in the US, most products are 30 to 55% kavalactones. Another possibility is that there may be individuals who have a genetic predisposition to have an unusual liver toxic reaction to kava. Research d
one in Hawaii indicates a toxic chemical (
) may be present in the stem peelings and leaves of the kava plant but not the root. As the demand for kava increased a few years ago, companies started buying the stem peelings and leaves along with the root while traditional kava users on the islands only used the root. This chemical is apparently toxic to liver cells whereas kavalactones found in the root are not, or not as much.
   Until we know the full details, it is best to restrict the use of kava to no more than 2 days a week.
Those with any kind of liver disease should not take it, nor those who are taking medicines or have a chronic medical condition. The interaction of kava with pharmaceutical medications or other supplements has not been tested. Even if it is eventually found that regular, long-term use is responsible for liver damage, we must keep things in perspective. There are thousands of deaths and hospitalizations each year from the use of aspirin and acetaminophen (Tylenol), yet they are available without a prescription and we don't hear sensational stories in the news about these fatalities. Overdoses of acetaminophen, the active ingredient in and other over-the-counter pain and fever relievers, is now the leading cause of acute liver failure in the US.
   I personally take kava a few evenings a month when I wish to relax after a long day. I plan to continue doing so, since, at this time, when used occasionally, it has few side effects and is safer than alcohol or pharmaceutical anti-anxiety drugs.

Food Chem Toxicol. 2011. Liver toxicity and carcinogenicity in F344/N rats and B6C3F1 mice exposed to Kava Kava. National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA.
In these studies rats and mice were administered kava extract orally by gavage in corn oil for two weeks, thirteen weeks or two years. Results from prechronic studies administered Kava at 0.125 to 2g/kg body weight revealed dose-related increases in liver weights and incidences of hepatocellular hypertrophy. In the chronic studies, there were dose-related increases in the incidences of hepatocellular hypertrophy in rats and mice administered up to 1g/kg body weight. This was accompanied by significant increases in incidences of centrilobular fatty change. There was no treatment- related increase in carcinogenic activity in the livers of male or female rats in the chronic studies. Male mice showed a significant dose-related increase in the incidence of hepatoblastomas. In female mice, there was a significant increase in the combined incidence of liver adenoma and carcinoma in the low and mid dose groups but not in the high dose group.

In vitro cytotoxicity of nonpolar constituents from different parts of kava plant (Piper methysticum).
J Agric Food Chem. 2006s
Kava roots, leaves, and stem peelings were extracted with methanol, and the resulting residues were subjected to partition with a different polarity of solvents (hexane, ethyl acetate, n-butanol, and water). Organic solvent fractions displayed a much stronger cytotoxicity than water fractions for all parts. The compound responsible for the cytotoxicity was flavokavain B.

Hepatic injury due to traditional aqueous extracts of kava root in New Caledonia.
Eur J Gastroenterol Hepatoly.
Traditional aqueous kava extracts were the most probable cause of hepatitis in two patients presenting with markedly elevated transaminases and hyperbilirubinemia. A consequent survey of 27 heavy kava drinkers in New Caledonia showed elevated gamma glutamyl transferase in 23/27 and minimally elevated transaminases in 8/27. We conclude that not only commercially available, but also traditionally prepared kava extracts may rarely cause liver injury.

Traditional kava beverage consumption and liver function tests in a predominantly Tongan population in Hawaii.
Clin Toxicol. 2007.
The liver function tests of 31 healthy adult kava drinkers were compared against a control group of 31 healthy adult non drinkers. Subjects were recruited from the general population, a kava bar, and Tongan drinking circles. The liver function profile included AST, ALT, ALP, GGT, and bilirubin (total and direct). Other tests included total protein, albumin, and screens for viral hepatitis and hemochromatosis when indicated. Chronic beverage consumption was associated with elevation of GGT in 65% of the drinkers versus 26% in the controls. ALP was elevated in 23% of drinkers versus 3% in the controls.

If kava may cause liver damage would it be helpful to take milk thistle with it or acetyl cysteine?
    A. Perhaps, but I do not know what the mechanism of that damage is, and whether milk thistle or acetylcysteine would help. The best approach is not to take the herbal product too frequently.

Driving under kava influence
Aust N Z J Public Health. 2015. Is driving under the influence of kava associated with motor vehicle crashes? A systematic review of the epidemiological literature. Kava is marketed as a herbal anxiolytic in several countries and is consumed recreationally in high doses in many indigenous Pacific and Australian Aboriginal communities. We reviewed the published literature examining the association (if any) between kava use and motor vehicle crashes (MVCs), MVC-related injuries or driving performance. No studies quantifying the effects of kava on MVCs or related injury were located.

Interactions with drugs and prescription medications
Prim Care Companion CNS Disorders. 2013. Toxic effects of psychotropics related to possible p450 enzyme inhibition by kava: report of 2 cases. Two cases of patients seen on the psychiatric emergency and consult service who developed severe side effects from psychotropic medications in the context of kava use are presented. In both cases, kava use may have affected the metabolism of the psychotropic medications, leading to serious side effects. Growing research indicates that kava most likely alters concentrations of coadministered psychotropics possibly by inhibiting cytochrome P450 enzymes.

I have taken kava supplement occasionally for depression. I suffer from SAD and adult ADD. It really helps with the calming overall, and seems to help me sleep through the night. With ADD there is a tendency to wake up and channel surf a couple times a night!

Natrol, buy Kava Kava, 200 mg, 30 Capsules
CAUTION: Kava is not the type of supplement, like vitamin C, that you take every day. At most use one capsule three times a week and take a full week off each month. In fact, it is preferable to use this herb no more than two times a week. Use on a daily basis may harm the liver in some individuals. In very rare cases, daily use can lead to severe liver harm that may result in total liver failure. Do not take a kava supplement if you are taking medications that can harm the liver, such as acetaminophen (Tylenol) or statin drugs for cholesterol such as Lipitor and Zocor. Do not take it if you are a heavy alcohol drinker. Kava does not seem to influence serotonin levels to any significant degree. However, one should always be cautious when combining herbs and pharmaceutical drugs, such as SSRIs, and dosages should be kept as low as possible.

Supplement Facts
Serving Size: 1 Capsule
  Amount Per Serving % Daily Value
Kava Kava Extract (Piper methysticum) (root) 200 mg *
Kavalactones 30% 60 mg *
*Daily Value not established.