This section is from the book "Botanic Drugs Their Materia Medica, Pharmacology and Therapeutics", by Thomas S. Blair. Also available from Amazon: Botanic Drugs, Their Materia Medica, Pharmacology and Therapeutics.
The leaves of Barosma betulina. Official in the United States, the British Empire, Japan, and Mexico.
Buchu contains a volatile oil which is excreted by the kidneys in combination with glycuronic acid. It produces a dilatation of the renal vessels and excites the renal epithelium to activity. The drug is diuretic, slightly antiseptic and carminative.
Buchu is not a very active agent. When an antiseptic influence is desired in the urinary tract, buchu is inferior to the chemical antiseptics, such as hexamethylenamine.
The infusion is an admirable vehicle for saline diuretics. As a general diuretic, buchu is disappointing. The fl., in doses of 15 to 60 minims, is adapted as a remedy in chronic affections of the genito-urinary mucous membrane, such as pyelitis, cystitis, and non-specific urethritis. It is of some value in old prostatic trouble.
Buchu is disagreeble to take, is expensive, and is being rapidly displaced by more effective agents.