What is Barberry?
The barberry grows wild throughout Europe but has been naturalized to many regions of the eastern US. M. aquifolium is an evergreen shrub native to the northwestern US and Canada. Barberry has spiny, holly-like leaves and is widely grown as an ornamental. Its yellow flowers bloom, then develop into red to blue-black oblong berries.
Berberis vulgaris, Berberis aristata, Mahonia aquifolium
Barberry also is known as holly barberry, Oregon grape, Oregon barberry, Oregon grapeholly, trailing mahonia, berberis, jaundice berry, woodsour, sowberry, pepperidge bush, and sour-spine
What is it used for?
The plant has a long history of use, dating back to the Middle Ages. Tribes in the Pacific Northwest used M. aquifolium to treat acne, and other Native Americans used Mahonia berries to treat scurvy. The sundried fruits have been eaten for fever-reducer and urine-production effects in Turkey. A preparation of the plant has been used to treat GI ailments and coughs. The alkaloid berberine was included as an astringent in eye drops, but its use has become rare. The fruits have been used to prepare jams, jellies, and juices. The use of the plant in traditional medicine has been limited by the bitter taste of the bark and root. However, multiple medicinal uses for barberry, including cancer, cholera, and high blood pressure have been listed.
Clinical applications may include use in treating diabetes and cholesterol disorders, although clinical trials are limited. Other activity includes antimicrobial, antioxidant, and anti-inflammatory effects. No clinical trials exist to support uses related to effects on the heart/blood vessel and central nervous systems or treating cancer.
What is the recommended dosage?
Daily doses of 2 g of the berries and 1.5 to 3 g daily of dry bark have been used; however, there are limited clinical studies to support barberry's varied uses.
Use with caution in the presence of irregular heart beat. Effective use in children has not been proven.
Avoid use. Documented adverse effects (including uterine-stimulant effects).
Barberry should be used cautiously with potentially toxic medicines such as cyclosporine.
GI symptoms (eg, nausea, vomiting, diarrhea), dizziness, and fainting have been reported. Effects on the heart/blood vessel system (eg, low blood pressure, decreased heart rate) and decreased breathing may occur with high dosages. Hypersensitivity has been documented.
Symptoms of poisoning are lack of energy, stupor and daze, vomiting and diarrhea, and kidney inflammation. A median lethal dose for berberine was noted as 27.5 mg/kg in humans.