Isobutylamide numbing agents of toothache grass, Ctenium aromaticum.

Ctenium aromaticum Panz. (Aegilops aromatica Walter, Monocera aromatica Elliott, Chloris monostachya Michaux,) is a grass restricted to wet areas of the coastal forest of the S.E. US. Knowledge of the pungent taste and numbing caused by chewing this grass dates from the 18th century or earlier (Walter, 1788; Michaux, 1805; Elliott, 1821), but use of this grass for allaying toothache was overshadowed by the more plentiful bark of toothache tree (Zanthoxylum americanum Miller, Rutaceae) in the same coastal areas of the southeastern US C. aromaticum was collected for this study in open, long leaf pine forests near Havelock, NC and deposited in the NC State University Herbarium (Voucher no. 124425-7).