Kava (Piper methysticum, Forst, Piperaceae) is from the South Pacific and comes from a family of peppers. Those of the Pacific Islands would use Kava during ritual ceremonies in a beverage to assist in relaxation. Now it's sold as a supplement in health food stores.
What is in Kava?
The kavalactones in Kava have skeletal muscle relaxation and sedative properties. Basically, properties to help deal with anxiety and sleeplessness/insomnia.
What does the research say?
In terms of generalized anxiety disorder (GAD), there was an RCT trial done that saw a reduction in anxiety comparing the kava group to the placebo group. It could have some short-term positive effects for those with moderate GAD.
So is it a placebo effect? Rather than the kava extract having a curative effect, it acts more as a placebo. When compared in a double-blinded placebo-controlled trial, kava could not reduce anxiety or insomnia compared to the placebo.
Are there any side-effects to using Kava extract?
It's not safe for the Islanders?
The World Health Organization (WHO) has determined that moderate consumption of kava in its traditional form has an "acceptably low level of health risk”.
Remember, it is traditionally consumed and not as a supplement.
Are Kava supplements?
Since there are many concerns associated with Kava, since 2003, they have banned kava extract in Canada and the European Union (EU) because there were at least 25 cases of liver toxicity linked to kava extract use.
In the US, Kava extract is still available however the FDA advises consumers about the potential risk of liver injury.
In summary...
There’s little to no evidence on any potential benefits, and there’s more evidence to show that it could do you harm. Taking high and consistent doses of Kava is NOT recommended.
There are safer alternatives to help treat anxiety or any sleep issues. As this out of the RD’s scope, referral to a psychologist or psychiatrist may assist in treatment.
Sources:
Boon H, Smith M. Safety of natural health products: clinical reports of adverse reactions and interactions with medications. Pharmacy Practice. 2000;16(6):41-7)
Clouatre DL. Kava kava: examining new reports of toxicity. Toxicol Lett. 2004;150(1):85-96.
Jacobs BP, Bent S, Tice JA, Blackwell T, Cummings SR. An internet-based randomized, placebo-controlled trial of kava and valerian for anxiety and insomnia. Medicine (Baltimore). 2005;84(4):197-207.
Russmann, S., Lauterburg, B. H., & Helbling, A. (2001). Kava hepatotoxicity. Annals of Internal Medicine, 135(1), 68. doi:10.7326/0003-4819-135-1-200107030-00036
Sarris J, Stough C, Bousman CA, et al. Kava in the treatment of generalized anxiety disorder: a double-blind, randomized, placebo-controlled study. J Clin Psychopharmacol. 2013;33(5):643-648.
Sarris J, Stough C, Teschke R, et al. Kava for the treatment of generalized anxiety disorder RCT: analysis of adverse reactions, liver function, addiction, and sexual effects. Phyother Res. 2013;27(11):1723-1728.