Kavalactone is the active ingredient in kava root, which contains the chemicals dihydrokawain, methysticum, and kawain. The kava plant is native to the Pacific islands, and is often used in ceremonial drinks and for medicinal purposes. Kavalactone can help reduce anxiety, insomnia, depression, and can promote a general relaxed state and sense of well-being.
Kava roots are typically prepared as a tea by soaking the roots or by pressing powdered roots through a strainer to push the kavalactone content into the beverage. Powdered root is also available in pill form, and kavalactones are sometimes isolated in liquid as well. Kavalactones have a numbing effect, making the lips, mouth, and tongue numb after drinking the tea. Kava root is sometimes used in topical creams and gels due to this numbing effect.
Most adults can take 150 to 300 mg of powdered kava root in capsule or liquid form one to three times a day to combat anxiety and depression. These mixtures should contain 30 to 70 percent kavalactones for maximum effectiveness and safety. Dosages may need to be altered for people with health concerns and patients who take other medications. Children should not drink kava tea or use other products containing kavalactones unless directed to do so by their doctors.
This substance has muscle-relaxant and sedative effects. It can be dangerous if used while driving or operating potentially dangerous machinery. Taking other sedatives or drinking alcohol at the same time as using kava can increase drowsiness.
One of the biggest concerns regarding kava preparations and kavalactones is the potential for liver damage. Kava products are banned in some countries, including Canada, Germany, and Switzerland, due to these concerns. People with liver disease or who take other medications that could damage the liver, such as acetaminophen, erythromycin, simvastatin, and fluconazole, should not use kava or kavalactone-containing products.
Some studies have shown liver damage occurring within a few months of using kava, so the herb should not be consumed for more than two months at a time without at least a four-week break. Patients who take kava regularly or use products with kavalactones for medical purposes should be monitored carefully by their doctors for signs of liver damage. Kava should also be avoided by pregnant and breastfeeding women and patients who suffer from Parkinson's or epilepsy, as the herb could make tremors and seizures worse.