Lemon balm is a perennial herb from the mint family. The leaves, which have a mild lemon aroma, are used to make medicine. Lemon balm is used alone or as part of various multi-herb combination products. Lemon balm is used for digestive problems, including upset stomach, bloating, intestinal gas (flatulence), vomiting, and colic; for pain, including menstrual cramps, headache and toothache; and for mental disorders, including hysteria and melancholia. Many people believe lemon balm has calming effects so they take it for anxiety, sleep problems, and restlessness. Lemon balm is also used for Alzheimer's disease, attention deficit-hyperactivity disorder (ADHD), an autoimmune disease involving the thyroid (Graves' disease), swollen airways, rapid heartbeat due to nervousness, high blood pressure, sores, tumors, and insect bites.