Description: Natural Order, Polygalaceae. This Family is represented in this country by the single genus polygala, which contains not less than thirteen species. Roots perennial, with a short and knotty caudex, and numerous short fibers. Stem annual, several from the same root, unbranched, six to twelve inches high, brownish-red below. Leaves alternate, sometimes scattered, oblong-lanceolate, dark green above, palish beneath, rough margined, nearly sessile, from one to three inches long. Flowers small, somewhat papilionaceous, in cylindrical spikes, which are terminal, and from two to three inches long; calyx of five persistent sepals, the upper and two lower of which are small, and the two lateral often of the color of the petals; petals three, white, connected with each other and with the stamen tube; shorter than the sepal wings; stamens six or eight, the filaments uniting below. Fruit a two-celled, flattened pod, inclosed in the persistent calyx, with a single seed in each cell; seeds with a long caruncle at the hilum. May and June.
This unattractive plant, with the calyx nearly concealing the corolla, is common on woody and rocky hillsides throughout the Middle and Southern States. The root is the medical part, and receives a portion of its name from the Seneca Indians, with whom it was in high repute as a remedy against snake bites. It is tapering, branched, crooked, wrinkled, yellowish-brown, with a white and woody center. The fresh roots have a strong and not always agreeable smell, which is less distinct in the dried roots. Its taste is at first sweetish, but afterward pungent, bitter, and rather acrid. Boiling water acts effectively upon the root, whose chief virtues reside in the corticle; warm water (105 deg.) is most suitable for making infusions; but the best solvent is diluted alcohol. Heat impairs it somewhat. Examination shows it to contain a volatile principle, supposed to be of an acid character; and a peculiar principle called polygalic acid, or senegin. It is obtained by treating the root with alcohol, removing a trace of fatty matter with ether, and then repeatedly washing with alcohol and water a precipitate that forms. When pure, it is a white and inodorous powder, and extremely irritating to the fauces. It is not an article of commerce.
Properties and Uses: Senega root is a distinct and persistent stimulant, chiefly influencing the respiratory membranes, but extending its influence to other mucous membranes, to all the secretory organs, the uterus, and the circulation. It promotes a flow of saliva, stimulates expectoration, causes a peculiar irritating sensation in the fauces, and proves nauseating (or even emetic and cathartic) in large doses. The principal use made of it, is as an expectorant in old coughs, asthma, and respiratory debility; but it is entirely too stimulating to use in recent cases, with inflammation or irritability of the respiratory passages, and is generally best employed when combined with a large excess of relaxing and demulcent expectorants, as comfrey. Some practitioners commend it as an ingredient in stimulating gargles, for putrid sore throat; and it enjoys some repute as a systemic stimulant in the treatment of secondary syphilis, mercurial cachexy, atonic amenorrhea, dropsy, and chronic rheumatism. Used in weak and warm infusion, it promotes perspiration and diuresis. The title "snake root," has been given to it from the reputed power of the warm infusion in casting out the virus of serpents; and certainly its stimulating action is sufficiently great to warrant the belief that its best use would be in those and other cases where it is necessary to sustain the circulation actively against the encroachment of animal poison–whether from serpents, or in the form of infiltrated pus or advancing mortification. I have twice employed the warm infusion to advantage in receding small-pox with its failing pulse. The agent is too commonly misapplied; and is used many times as if it were a relaxant expectorant, whereas it is one of the most positive and persistent of all stimulants to mucous membranes. Unless proper discrimination is made in using it, there is a strong liability of inducing painful irritation of the lungs, uterus, and kidneys. The polygalic acid, above mentioned, is said to have killed dogs when given in very large doses; and post-mortem examination revealed congestion of various mucous membranes.
Dose of the powder, from five to ten grains every three or four hours. Most commonly it is used as an ingredient with such articles as symphytum, glycyrrhiza, convallaria or althea, and made into an infusion. A decoction is prepared by adding a pint and a half of water to an ounce of senega and an ounce of licorice root, boiling down to a pint, and straining. One to two fluid ounces of this are used as an expectorant three or four times a day. A sirup is prepared by boiling four ounces of the root in a quart of water till the strength is obtained, straining with pressure, adding a pound of refined sugar, and evaporating so as to obtain a pint. Dose, one to two fluid drachms.
The Physiomedical Dispensatory, 1869, was written by William Cook, M.D.
It was scanned by Paul Bergner at http://medherb.com