Native to Europe, lemon balm is grown all over the world. It is grown not only in herb gardens or to attract bees, but also in crops for medicine, cosmetics, and furniture polish manufacturing. The plant grows up to 2 feet high, sometimes higher if not maintained. 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 the leaves, your fingers will smell tart and sweet, like lemons. The leaves are similar in shape to mint leaves, and come from the same plant family.

Insomnia and anxiety

Several studies show that lemon balm combined with other calming herbs (such as valerian, hops, and chamomile) helps reduce anxiety and promote sleep. Few studies have examined lemon balm by itself, except for topical use. For example, in one study of people with minor sleep problems, 81% of those who took an herbal combination of valerian and lemon balm reported sleeping much better than those who took a placebo. It is not clear from this and other studies whether lemon balm or valerian (or the combination) is responsible for the result.

The same is true of several studies for anxiety, which used a combination of herbs to reduce symptoms.

In another double-blind, placebo-controlled study, 18 healthy volunteers received 2 separate single doses of a standardized lemon balm extract (300 mg and 600 mg) or placebo for 7 days. The 600 mg dose of lemon balm increased mood and significantly increased calmness and alertness.

Herpes

Some studies suggest that topical ointments containing lemon balm may help heal cold sores caused by the herpes simplex virus (HSV). In one study of 116 people with HSV, those who applied lemon balm cream to their lip sores experienced significant improvement in redness and swelling after only 2 days. Other symptoms, such as pain and scabbing, did not improve. Both the people and their doctors reported that lemon balm ointment was highly effective. Another large study involving three German hospitals and one dermatology clinic showed that when lemon balm was used to treat the primary infection of HSV I, not a single recurrence was noted. The cream has also been found to reduce the healing time of both genital and oral herpes. Several animal studies also support the value of topical lemon balm for herpes lesions. And preliminary studies show that lemon balm exhibited a high, concentration-dependent activity against HIV infection.

Other uses

Some evidence suggests that lemon balm, in combination with other herbs, may help treat indigestion. Others reveal that lemon balm oil has a high degree of antibacterial activity. In one study, lemon balm showed adequate activity against Listeria monocytogenes and Staphylococcus auerus. And a few studies have found that lemon balm may help improve cognitive function and decrease agitation in people with Alzheimer disease.

Lemon balm supplements are made from the leaves of the plant. Essential oils made from lemon balm leaves contain plant chemicals called terpenes, which play at least some role in the herb's relaxing and antiviral effects. Lemon balm contains substances called tannins, which may be responsible for many of the herb's antiviral effects. Lemon balm also contains eugenol, which calms muscle spasms, numbs tissues, and kills bacteria.

Pediatric

Lemon balm may be used topically in children to treat cold sores. Speak to your health care provider for appropriate dosage for the child's age.

Adult

For difficulty sleeping, or to reduce indigestion, flatulence, or bloating, consult a knowledgeable provider for the specific dose to best fit your needs. Possible doses may be as follows:

• Tea: 1.5 to 4.5 grams (1/4 to 1 tsp.) of dried lemon balm herb in hot water. Steep and drink up to 4 times daily.

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 tea with cotton balls to the sores throughout the day.

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain components that can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, you should take herbs with care, under the supervision of a health care provider qualified in the field of botanical medicine.

Pregnant and breastfeeding women should not take lemon balm.

Lemon balm may potentially interact with the following medications:

Sedatives and thyroid medications: Lemon balm may interact with sedatives and thyroid medications. If you are taking sedatives (for insomnia or anxiety) or medications to regulate your thyroid, ask your doctor before taking lemon balm.

HIV medications: It is not clear whether lemon balm interacts with antiretroviral agents. At this time, avoid use of lemon balm if you are taking medication for HIV.