The oleaginous drug should not be confused with the essential oil, because with the term oleaginous drugs reference is made to fixed oils, butters and waxes.
Fixed oil and butter are predominantly glyceric mixtures, where fatty acids have almost always the same number of coals (from 16 to 22) and a different degree of saturation; in particular, butters have a lower concentration of unsaturated fatty acids.
Waxes are mixtures of fatty acids esterified with alcohols other than glycerol and in these mixtures it is more likely to find fatty acids with an odd number of carbon atoms.
The minority portion of oleaginous drugs (from one to ten percent maximum) is formed by a diverse series of lipophilic compounds: phytosterols (plant steroids), polyphenols, terpenoids, vitamin functions, flavonoids, steroid precursors (such as squalene ), and simple hydrocarbons. This non-glyceride fraction, called unsaponifiable fraction, characterizes the drug from the functional point of view and differentiates between them oils, butters and waxes. In other words, the health properties of the different oleaginous drugs are dictated by the prevailing chemical nature in their unsaponifiable fraction. However, all oleaginous drugs have emollient properties for topical use, since their lipophilic nature is akin to the lipid matrix of the skin and favors its distension. The internal use of these drugs is limited to fixed oils, which in this case show laxative and lubricating properties. The functional importance of oil drugs is mainly linked to their topical use.
