Herbal remedies range from the mild, such as chamomile (used to aid digestion) to the very potent, such as foxglove (used to make the heart medication digoxin). In fact, about 25% of pharmaceutical drugs are derived from plants. Herbal medicines tend to be gentler than drugs and produce fewer and milder side effects, says Dr. Merrell. Herbs come in a variety of forms, including teas, tinctures, capsules and tablets; the label on the product usually lists the recommended dosage.

· A review of 23 European clinical trials involving a total of 1,757 patients concluded that hypericum, the herbal remedy known as St. John's wort, was more effective than a placebo and just as effective as tricyclic antidepressants in alleviating mild to moderate depression. The herb was also shown to help relieve abnormal sleep patterns and anxiety, problems that often go along with depression. Critics say that some of the studies included in the analysis weren't well designed and that the dosages of the tricyclics were too low to be therapeutic, thus invalidating a comparison between the drugs and the herb. The benefits of St. John's wort should be better established in about three years, when researchers at Duke University Medical Center have completed their randomized study of the herb and Zoloft (a newer type of antidepressant that falls into the class of selective serotonin reuptake inhibitors) in depressed adults.

· A study in Germany compared two groups of people with sleep problems for 16 days. One group took 160 milligrams of valerian, and the other was given .125 mg of triazolam (Halcion). All the patients slept better and longer, but the valerian group was spared morning sedation and concentration problems, unlike those who took triazolam.

· Researchers at Jena University in Germany carried out a 25-week study in which 101 patients with anxiety disorders were randomly assigned either an extract of a pepper plant called kava kava (also known as kava) or a placebo. The herb far outperformed the placebo and was found to be so effective in reducing symptoms that study authors concluded that kava kava should be considered for treating anxiety problems instead of standard medications.

What to watch out for: St. John's wort, valerian and kava kava are all considered safe, but pregnant and lactating women and anyone who takes prescription drugs should talk with a doctor before using these herbs, says Mark Blumenthal, founder and executive director of the American Botanical Council in Austin, TX. A few more things you should know:

· St. John's wort has been shown in animals to increase the sk:in's photosensitivity, so avoid intense sunlight while taking the herb.

· A small number of people are very sensitive to valerian and may find that normal doses leave them feeling groggy in the morning; the simple solution is to lower the dose. In rare cases, the herb may cause agitation.

Consuming large doses of kava kava for long periods of time can cause dry patches of skin.

Visiting an expert: In Europe medical doctors routinely prescribe herbs, but in the U.S. naturopathic doctors and herbalists do most of the dispensing. The first visit lasts an average of 45 minutes and usually costs $30 to $60, according to Blumenthal. The practitioner will take a detailed history of your health, lifestyle and dietary habits to figure out the cause of your problem and then prescribe one or more herbs. To find a qualified herbalist near you, contact the American Herbalists Guild in Arvada, CO, at 303-423-8800. Or send a $5 check to the American Association of Naturopathic Physicians, 601 Valley St., Suite 105, Seattle, WA 98109, for a directory of members and a brochure. Insurance coverage varies by company and state.

On your own: Herbal products, like homeopathic remedies, are available in health food stores and some drugstores and supermarkets. Rob McCaleb, president and founder of the Herb Research Foundation in Boulder, CO, recommends using them as follows:

· For mild to moderate depression, try St. John's wort. Purchase a standardized extract (liquid, capsules or tablets) that contains .1% to .3% hypericin (the active ingredient in hypericum). Take 300 mg three times daily with food, since it can upset your stomach. Products that aren't standardized (such as teas) aren't your best choice, because you don't know how much of the active ingredient you're getting.

· For insomnia, take 150 mg to 300 mg of standardized valerian extract 30 minutes before going to sleep.

· For anxiety, use a standardized extract containing kavalactones (the active ingredients in kava kava). Take 300 mg daily in two or three doses - to help keep your blood levels of the herb consistent.