Pyrethrum

(pi-ref-thru?n). Pellitory; the root of An a cyclus pyrethrum, a plant of the order Compositse. P. is used as a sialagogue and masticatory in headache, toothache, and neuralgic affections of the face. It is employed either in powder or in the form of the tincture, Tinctura pyrethri (U. S. P.). 539