This section is from the book "Materia Medica Pharmacy, Pharmacology And Therapeutics", by W. Hale White. Also available from Amazon: Materia Medica Pharmacy, Pharmacology And Therapeutics..
An organic acid, prepared in a sufficiently pure condition by cooling commercial Oleic Acid to about 4I0 F.; 50 C, then separating and preserving the liquid portion. In case that it is obtained from Olive Oil the reaction is C,H5(C18H33O2)3+3H2O=3Hc18h33o2+C3H5(Oh3) (Glycerin).
A yellowish or brownish-yellow, oily liquid, having a peculiar, lard-like odor and taste; becoming darker and absorbing Oxygen on exposure to air. It becomes semi-solid at 40° F.; 4.40 C. Sp. gr., about 0.900.
It is rarely pure, usually containing Stearic and Palmitic Acids.
Oleic Acid is used to prepare Oleatum Hydrargyri, Oleatum Veratrinae, and Oleatum Zinci. There is some doubt whether the pharmacopceial oleates are chemical combinations or simple solutions.
Oleic acid is used as a solvent for remedies which it is desired to apply by means of cutaneous inunction, for it more readily penetrates the skin than fats and oils. Oleates are made from the alkaloids, not from their salts. If metals are employed, the oxides only are chosen. Copper oleate is also used for ringworm and indolent sores.