Botanical name: 

Daphne mezereum is an acrid shrub familiar to persons conversant with domestic medicine in mediaeval English times, being employed by the herbalists, and also, somewhat, by the medical profession of that day. It was recognized in Culpeper (175) as an acrid substance, generally applied externally, although it was given internally in dropsy and some other affections, about a dram of the dried bark of the tree being mixed with three parts of water, and taken internally. Hooper (325) in his Medical Dictionary states that a prevailing method of preparation was to macerate thin slices of the bark of the fresh root in vinegar and apply it externally. In Stephenson and Churchill's Medical Botany (614a) a Mr. Pierson serves as authority for a Dr. Russel, who, as did Mr. Pierson, reviewed the uses of the drug as a substitute for mercury and as an application in scrofulous and cutaneous affections, but with decided opposition to its use, on account of its exceeding acridity, a refreshing innovation in former orthodox medication. This imported, disagreeable drug crept into the United States Pharmacopeia and American practice by reason of the fact that it was made a constituent of the Compound Syrup of Sarsaparilla.

The History of the Vegetable Drugs of the U.S.P., 1911, was written by John Uri Lloyd.