What is valerian?
Valerian root (Valeriana officinalis) is an herb that has been used as a sleeping aid for more than 1,000 years. Many people (especially in Europe) still take it before going to bed. It's also an ingredient in many over-the-counter sleep products in this country.
Does it really help promote sleep?
Several small human studies have found that valerian root extract reduced the time to fall asleep and improved the quality of sleep. In one trial the herb worked as well as a prescription sleeping pill for insomnia. However, a 2007 review of 37 studies on valerian suggests that it doesn't work for everyone. Limited human evidence suggests that valerian extract might help ease stress, but more research is needed.
Researchers think that valerian works due to a combination of compounds. The herb seems to have a calming effect on the central nervous system. However, the research on valerian's sleep-inducing qualities is "inconclusive," according to the U.S. National Institutes of Health's Office of Dietary Supplements.
How safe is valerian?
Used as directed, valerian causes few side effects. Occasionally it might cause headache, insomnia or vivid dreams. However, very large amounts of valerian can cause more severe side effects, including dizziness. Valerian has been used safely in human studies for up to 28 days. No scientific information is available on the long-term safety of valerian, but long-term use might lead to withdrawal symptoms when valerian is stopped. As with other sleeping pills, its effectiveness may wear off over time. Avoid valerian when operating dangerous machinery; if you are pregnant, talk with your doctor before taking valerian. Children under three should not be given the herb, according to the NIH. Finally, never take valerian with prescription or over-the-counter sedatives, since it may intensify their effects.
What's the best way to take it?
Herbal experts recommend drinking valerian tea at bedtime to help you drop off to sleep. (Use a teaspoon of powdered root or liquid extract per cup of water.) Unfortunately, the tea smells like dirty socks, but you can avoid that unpleasantness by taking it in capsule form. Look for valerian at pharmacies and health food stores. Keep in mind that the government doesn't regulate herbal supplements as strictly as other drugs, so quality and potency can vary from bottle to bottle. In rare cases supplements may be contaminated with undesirable substances. Ask a pharmacist or naturopath to recommend a reputable brand.
Mayo Clinic. Valerian: A safe and effective herbal sleep aid? 2010. http://www.mayoclinic.com/health/valerian/AN02046
Wheatley D. Stress-induced insomnia treated with kava and valerian: singly and in combination. Hum Psychopharmacol Clin Exp 2001;16(4):353-6.
Willey LB, Mady SP, Cobaugh DJ, Was PM. Valerian overdose: a case report. Vet Hum Toxicol 1995;37(4):364-5.
Office of Dietary Supplements. Questions and Answers About Valerian for Insomnia and Other Sleep Disorders. 2008. http://ods.od.nih.gov/factsheets/Valerian.asp
Taibi DM, Landis CA, Petry H, Vitiello MV. A systematic review of valerian as a sleep aid; safe but not effective. Sleep Medicine Reviews. 2007; Jun; 11(3); 209-230.