The flowering tops and leaves of Hyssopus officinalis, Linné.
Nat. Ord.—Labiateae.

Botanical Source.—Hyssop is a perennial herb. Its stems are quadrangular, woody at the base, spreading, very much branched, and 1 foot or 2 in height; the branches are rod-like. The leaves are opposite, sessile, usually oblong-linear, or lanceolate, sometimes elliptical, sometimes narrower, acute, entire, punctate, green on each side, rather thick, and 1-ribbed underneath. The flowers are bluish-purple, seldom white, and borne in racemose, second whorls, consisting of from 6 to 15 flowers. The floral leaves are like those of the stem, but smaller. Outer bracts lanceolate-linear, acute, scarcely shorter than the calyx. Upper lip of the corolla erect, flat, emarginate; lower lip trifid, spreading, with the middle lobe larger. Stamens 4, protruding, and diverging; anthers with linear divaricating cells (L.—W.).

History and Chemical Composition.—Hyssop inhabits Europe and this country, being raised principally in gardens. It flowers in July. The tops and leaves are the medicinal parts; their odor is pleasantly fragrant, and their taste hot, spicy and somewhat bitter, which properties are due to a volatile aromatic oil, which rises in distillation both with water and with alcohol.

This oil of hyssop is limpid, neutral, and of a pale yellow or greenish-yellow color, camphoraceous in taste, neutral in reaction, and in odor resembling hyssop. Alcohol freely dissolves it. Its specific gravity is 0.88 to 0.98. It is an oxygenated oil, or, according to Stenhouse, a mixture of several such oils (Husemann and Hilger). Trommsdorf has shown Herberger's (1829) hyssopin to be merely an impure sulphate of calcium. Hyssop also contains fat, tannin, resin, mucilage and sugar. Water, by infusion, or alcohol extracts the active virtues of hyssop. It is said to contain some bitter principle and sulphur. In Mexico the Salvia axillaris, Sesse, is called hyssop.

Action, Medical Uses, and Dosage.—Stimulant, aromatic, carminative and tonic. Principally used in quinsy and other sore throats, as a gargle, combined with sage and alum, in infusion sweetened with honey. Also recommended in asthma, coughs, and other affections of the chest, as an expectorant. Ɣ The leaves, applied to bruises, speedily relieve the pain, and disperse every spot or mark from the parts affected. The infusion (herb, ʒiv to aqua Oj) may be given freely; the volatile oil, in doses of 1 or 2 drops.

King's American Dispensatory, 1898, was written by Harvey Wickes Felter, M.D., and John Uri Lloyd, Phr. M., Ph. D.