Used adjunctively for symptoms associated with hyperthyroidism
Lemon balm has been used since antiquity as a calmative agent, soothing frayed nerves and allaying anxiety. It is especially valued for its gentle pacifying action in children. Eclectic physician William H Cook, MD writes that lemon balm "soothes the nerves". Naturopathic physician William A. Mitchell Jr. discusses lemon balm in a chapter devoted to mild sedatives and relates that, "I prescribe 60 drops of the tincture three times daily as a mild sedative". Physician herbalist Rudolf Fritz Weiss writes that lemon balm "may be called a nerve remedy with a carminative element. The three main indications for Melissa are a nervous heart, a nervous stomach, and difficulties in going to sleep. It is predominantly used for the last of these three…"
Several herbal authorities corroborate the usefulness of lemon balm for quieting an over-active thyroid. Eric Yarnell and Kathy Abascal write that, "Various herbal medicines show enormous promise when it comes to hyperthyroid conditions… Lemon balm (Melissa officinalis) … shows promise in the treatment of hyperthyroidism…"
Botanist James Duke, PhD ascribes thyroid sedating effects to lemon balm, giving the herb his highest rating for Graves' disease (hyperthyroidism). He writes that, "In Europe, lemon balm, also known as Melissa, is often recommended along with bugleweed for treating Graves' disease. Studies show that lemon balm causes a decrease in blood and pituitary levels of TSH after a single injection, thus reducing thyroid hormone production."
Researcher Ryan Drum, PhD, meanwhile, considers lemon balm a primary treatment for Graves' hyperthyroidism, noting that, "Graves' disease seems very amenable to successful herbal intervention and control." Drum regards lemon balm as the most potent of three main herbs used for the condition, and he explains how lemon balm exerts its effects: "Melissa stops TSH from binding to its thyroid receptor sites, slows or even quells the uptake of iodine by the active transport sites on thyroid cell surfaces, suppresses the iodination of tyrosine residues in the follicular lumina by TPO, and appears to also impede stored thyroid hormone release from the thyroid gland. The results can be especially rewarding".