Herb library · Herb · Agathosma betulina, A. crenulata (formerly Barosma)
Buchu
A fragrant South African shrub whose leaves were a popular 19th-century remedy for the bladder and kidneys. It is sold today in teas and supplements for urinary health, but no clinical trials in people have been done.
Traditional use
The Khoisan peoples of South Africa used buchu for medicinal and spiritual purposes long before it was written down: as an infusion or steeped in brandy for the stomach, bladder and kidneys, colds, rheumatism and fever, and as a wash for wounds. Settlers carried it to Europe, and it was official in pharmacopeias from 1826 as a diuretic and for urinary infections, before antibiotics made it largely obsolete. Today its oil is used mostly in perfume and flavoring.
What studies show
No studies in people of this herb on its own yet. What is known of it comes from the traditions that use it.
- Insufficient
Urinary infections, kidney and bladder health: no randomized trials in people. Lab tests found only weak antimicrobial effects, and a 2022 review concluded that research to date has failed to confirm its traditional use.
- Insufficient
Blood sugar, weight and blood pressure: some rat studies of buchu water showed effects, but without human trials these remain unconfirmed, and the extracts used were not well characterized.
Be careful of
Cautions
- NoteBuchu contains pulegone, a compound that damaged the liver in rats given high doses of the essential oil. A. crenulata oil contains much more pulegone than A. betulina; pulegone does not dissolve in water, so this concern is mainly about the oil, not a water tea.
- NoteBuchu products are often adulterated, and claims made for them online (kidney, bladder and blood pressure support) have not been substantiated.
- Ask a clinicianTalk with a clinician or pharmacist before using this if you take prescription medicines, have liver or kidney disease, are pregnant or breastfeeding, or are giving it to a child.
From the old books
What herbals and dispensaries of the past printed. History, in their words.
“In trade, this valuable drug is often adulterated by the substitution of less powerful sorts of the same family of plants, which, although of a similar smell, are by no means equal to it in their therapeutical effects.”
“Buchu leaves have a strong odor, resembling somewhat that of pennyroyal, and a corresponding taste. When held up to the light translucent dots may be observed, owing to the fact that the under surface of the leaves is beset with scattered glandular oil-points.”
Sources
- Buchu (Agathosma betulina and A. crenulata): Rightfully Forgotten or Underutilized? (Front Pharmacol, 2022) (opens in a new tab) · NIH · read September 25, 2026
- 'Buchu' - Agathosma betulina and Agathosma crenulata (Rutaceae): a review (J Ethnopharmacol, 2008) (opens in a new tab) · NIH · read September 25, 2026
Reviewed September 25, 2026.