Oleum Anthemidis, B.P. Oil of Chamomile.
Oil of chamomile is obtained by distillation from the recently dried flowers of the Roman chamomile, Anthemis nobilis, Linn. (N.O. Compositae), cultivated in Europe and America. It occurs, when freshly distilled, as a blue liquid, becoming greenish and brownish-yellow under the influence of air and light, having a strong, but pleasant, aromatic odour, and a burning taste. It has a faintly acid reaction. Specific gravity, 0.905 to 0.915. Rotation, -1° (B.P. +1°) to +3°. Saponification number, 250 to 300. The oil from the German chamomile, Matricaria Chamomilla, Linn. (N.O. Compositae), has a specific gravity 0.930 to 0.940, and solidifies at 0°.
Soluble in alcohol (10 in 3), and forms a clear solution with 6 parts of alcohol (70 per cent.).
Constituents.—The oil consists chiefly of a mixture of esters of angelic and tiglic acids (two isomeric acids of the formula C5H8O2) with butyl and amyl alcohol, and butyric acid; it also contains an alcohol, anthemol, C10H16O, and a hydrocarbon, anthemene, C18H36, which forms crystalline needles melting at 63°. The body which causes the blue colouration of the freshly distilled oil has not been identified.
Action and Uses.—Oil of chamomile is employed for its aromatic carminative action on the stomach, and is given with purgative medicines to prevent griping. Pills containing 1 minim of the oil in each may be prepared by massing with soap and powdered liquorice root or powdered marshmallow root.
Dose.—¼ to 2 decimils (0.025 to 0.2 milliliters) (½ to 3 minims).