Kava
Kava (Piper methysticum), or kava kava ("intoxicating pepper"), is a pepper shrub native to some South Pacific islands. It has been used for centuries as a relaxing drink for use in ceremonies and to welcome visitors.
Uses:
- A German meta-analysis of six studies found that kava was effective for reducing anxiety. Another study found it helpful for sleep problems. But, kava was no better than a placebo in a Duke University analysis of three controlled studies.
- A population study in the Pacific Islands suggests that kava use was linked with a lower cancer rate.
- Kava is a diuretic that may help ease pain in the urinary tract, and is sometimes used for renal colic to relax spasms in the kidneys.
Forms: Capsules, powder, fluid extract
Cautions
- Kava is not for long-term use. If used, it should be in small doses for no longer than 2 months, and always under a doctor's care. Rarely, using kava longer can lead to liver damage, which is most often reversible. In a few cases, liver failure that required a transplant has occurred after using kava. For this reason, kava is no longer sold in Germany and Switzerland. (The kava drink used in the South Pacific is much weaker than the capsules sold here—but has also been linked to liver problems.)
- If you have Parkinson's disease or tremors, avoid kava. Kava reduces the effectiveness of L-Dopa. In one case, a woman with a family history of essential tremor developed severe Parkinson's disease after taking kava.
- Kava may cause drowsiness. Do not drive or use heavy machinery, or take kava with other sleeping pills or opium-based drugs.
- Don't take kava with alcohol or other drugs that can damage the liver, like acetaminophen (Tylenol®), steroids, methotrexate, the heart rhythm drug amiodarone (Cordarone®), or the anti-fungal drug ketoconazole (Diflucan®, Nizoral®, or Sporanox®).
- Kava shouldn't be mixed with alprazolam (Xanax®). Taking both together can cause coma.
- Do not use kava during pregnancy, nursing, or if you are depressed.
