This tender perennial has unusual olive-shaped flowers, and it grows to 30 cm tall. If you chew any part of the plant, you will experience a gentle numbing of the mouth, hence the name. Leaves are also used as an unusual addition for salads.

Of primary medicinal use are the roots and flowers of toothache plant. Chewing on the blooms of the toothache plant causes a local anesthetic effect and has been used to temporarily ease the pain of, yes, you guessed it — toothaches. Spilanthes flowers have also been utilized as a urinary antiseptic and even as a treatment for malaria by the indigenous people of the tropics. The active ingredient in Spilanthes is called Spilanthol. Spilanthol is an antiseptic alkaloid found throughout the entire plant but with the greatest amounts located in the flowers.

Sow indoors from April to May in soil 0.5 cm deep in trays. Plant out in June after the last frost. Sow outdoors direct in situ, and thin to 15 cm spacing. It is not frost hardy. Toothache plant tolerates most garden soils, and looks great in hanging baskets or pots.