Kava vs. Conventional Treatments for Anxiety

Comparing the Studies of Kava
with Conventional Treatments
Summary of chapter from Kava and Anxiety, by C. Grauds, RPh

Kava has become a popular herbal remedy for anxiety and the stresses of our modern lifestyle. From 1990 to 1997, kava sales in the U.S. increased by an astounding 473%. Part of the reason for kava's popularity lies in its unique properties. Kava has become the subject of scientific research only fairly recently. Studies show that kava induces a state of relaxation without interfering with cognition, memory, or alertness. Neither does kava produce tolerance or dependence, unlike many prescription anxiolytics. This article compares kava with conventional treatments for anxiety. Once again, clinical studies show that unlike most prescription anxiolytics, kava does not seem to impair mental functioning; it may even improve it.

Effectiveness Comparison
There are few effectiveness comparison studies on kava. What we do have are covered here. Note that they all compare kava with the benzodiazepine group of drugs, particularly oxazepam.
Two studies comparing kava with benzodiazepines, oxazepam and bromazepam, showed that there was no different in the effects. One 1990 placebo-controlled, double-blind clinical trial compared kavain with oxazepam in 38 out-patients diagnosed with anxiety associated with neurotic or psychosomatic disturbances. The anti-anxiety effectiveness of the two preparations was assessed by the Anxiety Status Inventory (ASI) and the Self-Rating Anxiety Scale (SAS) of Zung. The substances proved to be equivalent in the potency and nature of their effects, with no adverse reactions from either group.
Another 1993 double-blind study followed 174 patients with anxiety symptoms for a period of six weeks . Patients received either 300mg of a 70% kavalactone extract daily, 15mg/day of oxazepam or 9mg/day bromazepam. Improvement in HAM-A scores was roughly equivalent between groups. Nonetheless, few clinicians would agree that kava is equally effective as benzodiazepine drugs. The lack of significant differences in HAM-A scores is probably more a sign of the relative coarseness of the rating scale than truly equal efficacy.

Side-Effect Comparison
There is always concern that anti-anxiety medications or herbs may cause drowsiness or impair cognitive or motor functions. Barbiturates, most benzodiazepines, and some herbs such as valerian may cause drowsiness or impair functions. We would want to know if the same is true according to the research for kava.
There is one study comparing the benzodiazepine clobazam with kava to which we can look for some guidance. Synthetic kavain was compared to clobazam in a placebo-controlled, double blind study in 15 healthy volunteers. Subjects received placebo, various doses of kavain (200,400, and 600mg), or 30mg clobazam. EEG recordings, psychometric tests, and evaluations of pulse, blood pressure, and side effects were carried out. All three doses of kavain produced a significant improvement in intellectual performance (Pauli test), attention, concentration, reaction time, and motor speed. The opposite findings were observed after clobazam. Dose-dependent changes in EEG brain waves showed that at 200mg kavain improved drive, mood, well-being, and wakefulness compared to the placebo. At 600mg kavain produced sedation comparable to 30mg clobazam.
These research findings seem to support similar subjective comments by patients or physicians who have taken kava or benzodiazepines. Unlike most prescription anti-anxiety medications, kava does not seem to impair mental functioning; it may even improve it.

Combining Kava with Other Treatments
As was already mentioned, there's no particular risk in trying kava before seeking medical attention, because if it doesn't work nothing has been lost.
Few patients taking benzodiazepines such as Xanax manage to successfully make the switch to kava. Those who wish to try it must first gradually stop anti-anxiety medications under doctor's supervision rather than overlapping treatments. However, the transition from buspirone to kava can generally be undertaken without difficulty under the guidance a physician.
Just as anti-depressants are often combined with anti-anxiety medications in the treatment of anxiety, St. John's wort/kava combinations are recommended by many herbalists. While the safety of this combination treatment is not established, there have been no reports of harm. Similarly, kava is frequently combined with other herbal tranquilizers, such as valerian, hops, and passionflower, without apparent adverse consequences.

Summary
Kava has become the subject of scientific research only fairly recently. While the research on comparisons of effectiveness of kava with benzodiazepines show that they are roughly equivalent, few clinicians would agree that kava is equally effective as benzodiazepine drugs.
In comparing the side-effects of kava with benzodiazepines, research shows that kava does not cause drowsiness or impair cognitive or motor functions. In fact, kava has been shown to improve mood, well-being, and drive.
We have no research on the combining of kava with medications or other herbs. The consensus is, however, that it is best to gradually stop prescription medications under the guidance of a physician before starting kava. In combining other herbs with kava, many herbalists frequently recommend herbal combinations with kava, and there have been no adverse reports from these combinations.

Addendum: In 2001, several of these countries, including Germany, banned or pulled kava from health store shelves, due to reports of kava-related liver damage. In the United States, studies have not substantiated the claims of liver damage, and the Food and Drug administration have not pulled the herb. Researchers here believe that any kava-related liver damage would have been caused by excessive dosage and/or continual usage of the herb, a probable byproduct of our "taking more is better" Western culture. Certainly, South Sea islanders have never exhibited any liver damage symptoms.