History and Description.—Juniper is common to Europe and this country, growing in dry woods and hills, and flowering in May. The fruit or berries are the medicinal parts; those which are imported from the southern parts of Europe are the best. The American berries possess less medicinal virtue, and are seldom employed. Juniper berries are about the size of currants, of a purplish-black color, shrunken, marked at the top with a triradiate groove, and at the base with the bracteal scales; they contain 3 seeds. Their odor is peculiar, terebinthine, and aromatic, and their taste terebinthine and sweetish, succeeded by some bitterness; these qualities are due to an essential oil, which may be obtained by distillation with water. They yield their properties to hot water or alcohol. An empyreumatic oil—oil of cade (see Oleum Cadinum), or huile de cade, is obtained in France by dry distillation of the wood of Juniperus Oxycedrus, Linné.
Action, Medical Uses, and Dosage.—Both the berries and oil are stimulating, carminative, and diuretic. The oil is said to act like copaiba in arresting mucous discharges, especially from the urethra. It is contained in the spiritous liquor called Hollands, one of its best forms as a diuretic. Five minims of the oil, with 1 fluid drachm of nitrous ether, given 3 times a day in any common vehicle, produces diuresis in dropsy when other means fail. Combined with an equal part of watermelon seeds, and made into an infusion, I have cured several cases of ascites occurring in children, having them to make free use of it (King). The berries are employed principally as an adjunct to other diuretics, and have been found efficient in gonorrhœa, gleet, leucorrhœa, cystirrhœa, affections of the skin, scorbutic diseases, etc. Pyelitis, pyelo-nephritis, and cystitis when chronic, and particularly when in old people, are relieved by juniper. Uncomplicated renal hyperemia is cured by it. The indications are a persistent weight or dragging in lumbar region. Dose of the berries, from 1 to 2 drachms; of the oil, from 4 to 20 minims. The infusion (berries, ℥i; aqua, Oj), may be given in wineglassful doses, a pint being taken in a day. It is very useful in the dropsy following scarlatina, and other infectious diseases, and may be combined with acetate or bitartrate of potassium if desired. Oil of Cade has been successfully employed in parasitic skin diseases, moist eczema, and psoriasis.