Herbs and Supplements For the Promotion of Sleep - What is the Evidence?
Valerian is an extract of the Valerian root (Valeriana officinalis) and is widely prescribed in Europe for the treatment of insomnia. Valerian is available as a supplement in the US. In an early study, 166 volunteers were given Valerian, a Valerian containing commercial product, or placebo. After three doses, Valerian was associated with a significant decrease in the time it takes to fall asleep and improvement in sleep quality. Sleep was better in the pure Valerian extract than in the proprietary product Hova®, which contains Valerian extract. This study did not measure, however, how well the blinding worked, which is important because Valerian has a strong and distinctive smell.
An uncontrolled study of 54 subjects showed a reduction in heart rate, blood pressure, and subjective distress to a stressful task after receiving Valerian. This study suggests that valerian may have sedative properties. Another study of 16 patients with sleep disorders randomly assigned patients to two doses of Valerian or a placebo nightly and measured EEG measures of sleep as well as subjective reporting of sleep quality while patients were sleeping in a sleep laboratory. Side effects include vivid dreams in as many as 16% of cases, and less commonly drowsiness, depression, dizziness, headaches or blurred vision. When the patients were given a single dose of Valerian, the lower does had no effects on subjective or EEG measures of sleep. Because of inconsistent results and no clear mechanism by which Valerian could treat insomnia without significant side effects I think that large, properly controlled trials are needed to determine if Valerian is useful for insomnia. However in the mean time since Valerian does not have major side effects I wouldn’t necessarily discourage you from using it.
Kava (or Kava-kava) is an extract of the roots of the Polynesian plant Piper methysticum used in the South Pacific for its sedative, aphrodisiac, and stimulatory effects. Active compounds include the kava pyrones, which may have effects on the brain. Several controlled trials have shown that Kava reduces anxiety in patients with anxiety disorders. One study looked at 24 subjects with stress induced insomnia treated for six weeks with 120 mg of kava daily followed by two weeks off treatment and then Valerian for another six weeks. Both Kava and Valerian improved sleep (decreased onset, longer sleep time) and reduced stress severity. Side effects of Kava include dizziness (12%), dry mouth, gastric disturbance, diarrhea, dizziness, drowsiness, depression, and more rarely liver failure, which has caused it to be banned in some countries. Because of the very real risk of liver failure and possibly death I would not recommend Kava for the treatment of insomnia.
Melatonin is a hormone that occurs naturally in the body and is involved in the regulation of the wake-sleep cycle. Melatonin can decrease the time it takes to fall asleep but overall has no effect on sleep time. It is popular with travelers. By taking melatonin, however, keep in mind that you are meddling with your own body’s hormonal status, which can have risks. For instance, taking melatonin may affect growth or reproductive function. Other side effects include abdominal cramps, confusion, depression, drowsiness, nausea and vomiting. I don’t see any major risks for melatonin so if you want to try it on your next plane trip across the Atlantic feel free.
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