Botanical name: 

The rhizome of Eryngium yuccifolium, Michaux (Nat. Ord. Umbelliferae). A swamp and wet prairie plant found from Virginia to Texas. Dose, 10 to 40 grains.
Common Names: Eryngo, Water Eryngo, Button Snakeroot, Rattlesnake's Master, Corn Snakeroot.

Principal Constituents.—(Has not been analyzed.)
Preparation.—Specific Medicine Eryngium. Dose, 5 to 40 drops.

Specific Indications.—Burning pain, with renal, vesical or urethral irritability; painful micturition, with frequent urging to urinate; frequent, scanty and scalding urination; scanty urine, with frequent and ineffectual attempts to urinate; deep-seated pain in bladder extending into the loins; profuse mucous discharges.

Action and Therapy.—The root of eryngium, when chewed, causes a profuse flow of saliva; in large doses it is emetic. Its chief properties are those of a diuretic and expectorant. While of considerable value in chronic laryngitis and bronchitis with free and abundant secretion of muco-pus, it is of most service in irritation of the bladder and urethra, with itching, burning, and constant urging to urinate. It is also useful in dysuria with tenesmus. For that condition in women during or following menstruation, or during the menopause, when sudden chilling throws the burden of excretion upon the kidneys, it is invaluable to control the bladder symptoms—as fullness, burning, itching, frequent attempts at urination, or when every movement of the body is accompanied by the involuntary passing of urine. We know of no remedy that acts so promptly and satisfactorily in such conditions. In the male it relieves uneasy sensations, with burning and itching throughout the vesical, prostatic, and urethral tracts, especially when following gonorrhea or gleet. It is not contraindicated by inflammation and is of great value in acute cystitis, with deep-seated, burning pain, and where normal secretion is scanty and pathologic catarrh is more abundant. It acts well with apis or gelsemium, with the latter especially when there is a hyperaemic state of the bladder. It relieves the burning pain of urination in gonorrhea. It is indicated to relieve the difficulties of voiding urine from the presence of gravel and of chronic nephritis; and it restrains the excessive discharges of chronic cystitis. When spermatorrhea is provoked by urethral irritation, eryngium serves to limit the frequency of losses.

Sometimes eryngium will be found useful in digestive disorders, with persistent gastric irritation and mucous diarrhoea. In these cases the tongue is red and tender, nausea is marked, and there is a strong for food.

The Eclectic Materia Medica, Pharmacology and Therapeutics, 1922, was written by Harvey Wickes Felter, M.D.