Just as mint is known for its soothing effects on the stomach, lemon balm is also used to ease pain and discomfort associated with digestion, including gas and bloating. Lemon balm also calms and relaxes, easing away stress and nervous anxiety, and can help you get to sleep, and has been used for this purpose as far back as the Middle Ages. Today, it is often combined with other calming, soothing herbs, such as valerian, to enhance the overall relaxing effect.

Even before the Middle Ages, lemon balm was used to lift the spirits, and to help heal wounds and reduce the swelling and pain of insect bites. Research also supports its use for cold sores, or lesions due to herpes viruses. European ointments for cold sores and herpes sores contain high concentrations of lemon balm. Patients say these ointments work better than some prescription medications in easing pain and preventing sores from coming back, and their health care providers confirm this.

Lemon balm is also used to treat headaches, menarche (delayed menstruation), and chronic fatigue syndrome. It also seems to help in the treatment of a thyroid disorder called Graves' disease. While clinical trials are lacking, the tests that have been done tend to support the herb's many uses. For example, lemon balm essential oil exhibited the ability to relax muscles in laboratory animals, including the smooth muscles that line the digestive tract. Studies also suggest that lemon balm extracts affect the thyroid hormones in a way that benefits people with Graves' disease.

Lemon balm comes from Europe and is now grown all over the world. It is grown not only in herb gardens, but also in crops for medicine, cosmetics, and furniture polish manufacturing. The plant grows up to two feet high, sometimes higher if left untended. In the spring and summer, clusters of small, light yellow flowers grow where the leaves meet the stem. The leaves are very deeply wrinkled and range from dark green to yellowish green in color, depending on the soil and climate. If you rub your fingers on them, your fingers will smell tart and sweet, like lemons. The leaves are similar in shape to mint leaves, and in fact, come from the same plant family.

Lemon balm preparations are made from the leaves of the plant. Essential oils made from lemon balm leaves contain plant chemicals called terpenes, which cause at least some of the herb's sedative and antiviral effects. Lemon balm also contains ingredients called tannins, which are thought to cause many of the herb's antiviral effects. It also contains eugenol, which calms muscle spasms, numbs tissues, and kills bacteria.

Lemon balm is available as dried leaf that can be bought in bulk. It is also sold as tea, and in capsules, extracts, tinctures, and oil. The creams used in Europe, which contain high levels of lemon balm, are not currently available in the United States, but teas can be used on the skin by applying it with cotton balls.

In general, you should read the manufacturer's suggestions for use when taking any herbal product, and consult with your health care provider for brands and dosages that he or she recommends.

For difficulty sleeping, or to reduce stomach complaints, flatulence, or bloating, choose from the following:

• Tea, using 1.5 to 4.5 g herb, several times daily
• 2 to 3 ml tincture three times daily, or the equivalent in fluid extract or encapsulated form

For cold sores or herpes sores, steep 2 to 4 tsp of crushed leaf in 1 cup boiling water for 10 to 15 minutes. Cool. Apply with cotton balls to the sores throughout the day.

No side effects or symptoms of toxicity have been reported with lemon balm use, but because it is used to bring on menstruation, do not use it if you are pregnant.

Although it has not yet been demonstrated in scientific studies in humans, lemon balm may interfere with thyroid medications. If you are taking medications to regulate your thyroid, you should not use lemon balm.

No specific interactions between lemon balm and conventional medications are known to have been reported in the literature to date.

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