Acmella oleracea (syn. Spilanthes oleracea, S. acmella) is a species of flowering herb in the family Asteraceae. Also known as the toothache plant. Its native distribution is unknown, but it is likely derived from Brazil and widely grown in tropical climates, such as Hawaii. It is grown as an ornamental and it is used as a medicinal remedy in various parts of the world. A small, erect plant, it grows quickly and bears gold and red inflorescences.
For culinary purposes, small amounts of shredded fresh leaves are said to add a unique flavor to salads. Cooked leaves lose their strong flavor and may be used as leafy greens. Both fresh and cooked leaves are used in dishes. They are combined with chilis and garlic to add flavor and vitamins to other foods.
The flower bud has a grassy taste followed by a strong tingling or numbing sensation and often excessive salivation, with a cooling sensation in the throat. The buds are known as “buzz buttons”, “Szechuan buttons”, and “electric buttons”.