Buchu is slightly tonic, owing to its bitter principle. It is also a stimulating diuretic, and has some alterative power.
The leaves of Ruta graveolens, or garden rue. The active principle is a volatile oil, of hot and bitter taste. Rue is a carminative and emmenagogue. In large doses it is irritant and will cause abortion. It is less powerful than savine.
Dose of the oil, Oleum Rutae, i.-0.05 mil.