Synonym.—Oil of Canadian Fleabane.
Oil of erigeron is obtained by distillation from the herb Erigeron canadensis, Linn. (N.O. Compositae), which is frequently found growing in the peppermint fields of America. It is official in the U.S.P. It occurs as a pale yellow, mobile liquid, which on exposure to air rapidly resinifies, and becomes darker in colour and viscid. It has a peculiar, aromatic, persistent, odour, suggesting caraway, and an aromatic, slightly pungent taste. Specific gravity, 0.850 to 0.870 (0.845 to 0.865 at 25°); rotation, +52°; boiling-point, 175°.
Soluble in an equal volume of alcohol, forming a clear solution, and having a neutral reaction.
Constituents.—The oil consists chiefly of dextro-limonene, but also contains small quantities of aldehydes, and sometimes terpineol, which however is regarded as a decomposition product.
Action and Uses.—Oil of erigeron resembles in its action oil of turpentine, but it is less irritating. It has been employed to arrest haemorrhage from the lungs, uterus, or alimentary tract, but the drug has no such action. The oil may be administered in capsules, or as an emulsion.
Dose.—1/4 to 2 mils (5 to 30 minims).