Lemon Balm Leaf (Melissa officinalis). The best application of lemon balm is as a calming diaphoretic for the treatment of fevers. It’s gentle properties and pleasant flavor, is suitable especially for children and those who tend to be sensitive to the strong bitter flavors of most herbs. It removes tension from the body and is effective as a treatment for nervousness and tension. It can also be used for upset stomach and gas. Used as an external ointment it is highly effective in relieving the painful symptoms of Herpes Simplex.