Oleum Valerianae.—Oil of Valerian.
Related entry: Valeriana.—Valerian
The essential oil distilled from the root of Valeriana officinalis, Linné.
Preparation and Description.—The root of Valeriana officinalis distilled with water yields about 1 per cent of volatile oil. When freshly prepared it is a yellowish-green, faintly acid, thin liquid, the odor of which is not unpleasant. Upon exposure to the air it becomes dark-brown, viscid, strongly acid, and of a very disagreeable odor, owing to the liberation of valerianic acid (C5H10O2). Fresh oil of valerian has a specific gravity of 0.93 to 0.96 and is optically laevo-rotatory.
Chemical Composition.—The characteristic constituent of oil of valerian is bornyl- (borneol-) valerianate (Bruylants, 1878), an ester which undergoes spontaneous decomposition into borneol and valerianic acid when the oil is exposed to air. The stearopten sometimes deposited in old oil is borneol. According to Gerock (1892), about 9.5 per cent of this ester is present, with 1 per cent, each, of bornyl-formiate, acetate, and butyrate. Upon saponification of these esters with caustic alkali and fractionating the resultant oil, the hydrocarbons l-pinene and l-camphene were found in the lowest fractions, then followed l-borneol, terpineol, a sesquiterpene, and an alcohol, C15H26O (Olivieri, 1893). From the saponification water, Olivieri isolated a crystallizable, laevo-rotatory alcohol (C10H20O2), melting at 132° C. (269.6° F.). The highest fractions of oil of valerian, according to Prof. Flückiger (1876), contain a blue oil (Gildemeister and Hoffmann, Die Aetherischen Oele, 1899); its taste is warm and camphoric. Caustic alkalies saponify the oil uniting with its valerianic acid to form valerianates.
Action, Medical Uses, and Dosage.—Oil of valerian possesses the properties of the root in a concentrated degree, and may be substituted for it in all cases where the root is applicable. It has been found especially useful in hysteria, chorea, restlessness, etc. An efficient preparation for nervous, sleepless, and hysterical cases is composed of: Tincture of lupulin, tincture of hyoscyamus, of each, 4 fluid ounces; camphor, 1 drachm; and oil of valerian, 22 minims. Mix, and give 1 or 2 fluid drachms for a dose. The dose of the oil of valerian is 2 to 6 drops in alcoholic solution, pill, or emulsion.