Fever Bark tree - Alstonia spp. (Apocynaceae)

Medicinal Use of Fever Bark – Alstonia spp. (Apocynaceae)


Evergreen trees growing to 49 ft (15 m). Have glossy oblong leaves and creamy white, star-shaped flowers.

Habitat & Cultivation

A. constricta is native to Australia, and A. scholaris to Australia and Southeast Asia. Both are now found in tropical regions around the world.

Parts Used

Stem bark, root bark.


The bark of both species contains indole alkaloids. A. constricta contains reserpine, a powerful hypotensive.

Medicinal Actions & Uses

Fever bark has been taken to treat malarial fever (and has been called Australian quinine), but its efficacy against malaria remains unclear. The bark is antispasmodic and lowers blood pressure, and is now used mainly to reduce high blood pressure. Strongly bitter, the bark is also taken to treat diarrhea.


Take only under professional supervision. Fever bark is toxic in large doses. The herb is subject to legal restrictions in some countries.