Side Effects and Health Risks of the Herbal Medicine Kava

Natural medicines are popular alternatives to the use of prescription medicines. There is a prevailing belief among many users of nutritional supplements and herbal medicines that these options are gentler and safer than prescription medications. Unfortunately, this is not always the case. The use of certain natural medicines without guidance from a health care professional can be downright dangerous, and sometimes deadly.

Kava kava is an herbal medicine that has many uses such as the treatment of anxiety, restlessness, insomnia and migraines. However, this medicine is also an excellent example of an herbal treatment that carries significant side effects and health risks. In fact, kava has been banned from the market in Switzerland, Germany and Canada, and several other countries are considering a similar ban.

When taken orally, kava can cause numerous side effects including:

-stomach upset
-headache
-dizziness
-drowsiness
-enlarged pupils and disturbances of oculomotor equilibrium
-dry mouth
-allergic skin reactions
-extrapyramidal side effects, such as involuntary twisting movements of the head and trunk
-impaired ability to drive or operate machinery

Kava can also pose a significant health risk in certain individuals due to its hepatotoxic, or liver damaging, effects. There have been at least one hundred reported cases of hepatotoxicity following the use of kava products.

Some individuals may be more susceptible to kava liver toxicity than others. These susceptible individuals include those with underlying liver dysfunction, such as cirrhosis or chronic hepatitis, or those with poor liver metabolism of specific kava constituents. Poor kava metabolizers have a deficiency in the liver cytochrome CYP2D6 isoenzyme. Up to 10% of people of European descent have a genetic deficiency of CYP2D6 and may be at increased risk for the liver toxic effects of kava.

In people who do have an increased susceptibility to kava toxicity, symptoms can begin within three to four weeks of kava use. Liver damage is more often seen with the prolonged use of very high doses of kava supplements or teas. However, in some people even short-term use of kava in typical doses might cause acute liver toxicity. The use of kawa kawa for as little as one month to three months has even resulted in death. Signs and symptoms of liver damage include:

-yellowed skin (jaundice)
-fatigue
-dark urine
-elevated liver function tests
-hepatomegaly (enlarged liver)
-encephalopathy

Despite the known side effects and health risks of kava kava, this herb can be taken safely and effectively by the majority of people. Similar to prescription medicines, the side effects and adverse health effects of kava only occur in a small percentage of individuals. In order to safely utilize the benefits of kava, individuals should work with a health care practitioner to determine the appropriate dose and frequency. Additionally, safe long term use of kava should include routine monitoring of liver function.

Resource:

Natural Medicines Comprehensive Database