Originally published in The Ottawa Citizen May 4, 2004
Original Title: Herbal Reality
Do herbal preparations really live up to their claims?
There are many anecdotal reports that they do make a difference and help people with a variety of ailments. Many websites purport to give information but, for the average consumer, it can be difficult to separate the facts from bias.
Some sites act as fronts for retailers; others have a political axe to grind.
The “natural” label so often cited for safety of herbal preparations is misleading. They contain many chemical compounds that can be therapeutic or toxic. As such, they require the same degree of evaluation as prescription medications.
In future columns I will present the latest evidence-based information on some of the more popular herbal preparations you may see every day in the stores. Indeed, with ongoing scientific inquiry, we will learn more about their safety and efficacy.
Take the herbal remedy valerian, for example.
People use valerian root, found in North America, Europe and Asia, to treat insomnia and anxiety. Valerian is widely available at pharmacies and health food stores, in capsules and pills.
Testing has focused on valerian as a single ingredient preparation and not in combination with other herbs.
Valarian’s chemical makeup includes compounds such as valpotriates and valeric acid that have direct sedative effects on the nervous system.
One double-blind placebo controlled study evaluated valerian extract’s ability to reduce sleep latency (the time it takes to fall asleep) and night awakenings and to improve sleep quality and dream recall. The extract did help people fall asleep faster and improved the quality of sleep, but had no effect on the other two measurements.
These results were best in people who described themselves as poor sleepers and smokers. Valerian had little to no effect on people who were already good sleepers.
Other small limited studies also showed improvement in sleep latency. However, most of the studies under review used different criteria to choose the study participants and varied the dosages. The small numbers make it difficult to come to a definitive conclusion about its ability to treat insomnia.
Doses between 300 to 600 milligrams per day did not produce any daytime sleepiness, although patients using 400 to 900 milligrams per day two hours before bedtime had the greatest benefit.
Valerian seems to be comparable to low-dose prescription sleeping pills such as the benzodiazepines lorazepam and oxazepam, among others. Continuous nightly use for several days to four weeks may be necessary before it provides significant relief. The potential advantage of valerian over benzodiazepines is the lack of addictive potential and lack of morning grogginess.
There is limited data regarding its ability to treat anxiety. Larger studies are needed before drawing any conclusions.
Valerian products produced from the species Valeriana officinalis are relatively safe, at recommended dosages, with minimal side effects and drug interactions. Side effects may include minor digestive system discomfort, dry mouth, vivid dreams and, very rarely, a mild stimulant effect.
Excessive dosing is associated with similar withdrawal effects as seen with benzodiazepine sleeping pills. Signs of toxicity may include trouble walking, hypothermia and increased muscle relaxation.
Valerian may augment the effects of barbiturates, anesthetics and other central nervous system depressants, and should not be used with alcohol. The safety of valerian has not been well evaluated for children or for women who are pregnant or nursing, and it is not recommended for use by such individuals or by women who may become pregnant.
Should you decide to use valerian, choose a product made from the root (or rhizomes) of Valeriana officinalis since most clinical research used this plant. Products made from other species can be rich in a compound, didrovaltrate, that is toxic to cells in laboratory tests.
The bottom line is that more rigorous studies are needed to flesh out which chemical component in valerian provides efficacy and its biochemical properties.
© Dr. Barry Dworkin 2004
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