Yohimbe
Pausinystalia johimbe

Family: Rubiaceae

What it is like

Pausinystalia johimbe or commonly known as Yohimbe is native to western and central Africa. It is evergreen and grows up to 30m tall with a straight bole that can be up to 60cm in diameter. The leaves are oval-shaped. The bark is gray to reddish-brown. Yohimbe is used medicinally as stimulant, anti-diuretic, hypotensive, and bitter herb. It has aphrodisiac effects and is hallucinogenic. In particular, it is used in the treatment of impotence, frigidity, and angina. The bark is also a source of tannins. The wood is used as firewood and construction material. There is no known edible use of this plant.

Pausinystalia johimbe is an evergreen Tree growing to 25 m (82ft) by 20 m (65ft) at a medium rate. See above for USDA hardiness. It is hardy to UK zone 10. Suitable for: medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.

Height (m): 25

Where it is found

A middle-storey tree of forests. Occurs mainly in closed canopy forest, most commonly in coastal forest, although not widespread throughout its range.

West tropical Africa - Nigeria, Cameroon, Equatorial Guinea, Gabon, Congo, DR Congo..

Conservation Status: This taxon has not yet been assessed

Countries/locations it is found in

How it is used

Food

Rating: 0

Medicine

Rating: 5

The bark contains up to 6% of a mixture of indole alkaloids, the principle one being yohimbine (which is also known as aphrodine), plus pigments and tannins. The alkaloids have a cerebral stimulant action at low doses, but are highly toxic in large doses. Yohimbine has been shown to block the release of adrenalin and, in the correct dose, act as a sexual stimulant. It is the source of the only clinically-proven cure for impotence and has long been used as a traditional stimulant in Africa. Yohimbe is a bitter, warming, anti-diuretic, hypotensive and vasodilating herb with reputedly aphrodisiac effects. It has a stimulant effect upon the heart, increasing heart rate and blood pressure; has a locally anaesthetic action similar to that of cocaine but without being mydriatic; is a mild stimulant that can help to prevent drowsiness; and is hallucinogenic. The vasodilating action of yohimbe is particularly strong on the sex organs, hence its aphrodisiac action. The bark is taken internally, either as a powder or as a decoction. It is used particularly in the treatment of impotence, frigidity and angina. It is also used as a performance enhancer for athletes, and as a remedy to increase the clarity of the voices of singers during long festivals. The bark can be harvested at any time of the year. The use of this herb is subject to legal restrictions in some countries.

Anaesthetic: Numbs the feeling in a local or general area of the body.

Aphrodisiac: Increases the sexual appetite.

Cardiac: Used in the treatment of heart problems.

Hallucinogenic: Causes the mind to hallucinate.

Hypotensive: Reduces blood pressure, it is used in the treatment of high blood pressure

Stimulant: Excites or quickens activity of the physiological processes. Faster acting than a tonic but differing from a narcotic in that it does not give a false sense of well-being.

Vasodilator: Widens the blood vessels, thereby reducing blood pressure.

Other

Rating: 2

Other Uses The bark is a source of tannins. The inner bark is utilized as straps for panniers. The tree produces very little sap-wood, the major fraction being an ocreous-yellow heart-wood. The wood is flexible, so is widely used as a snare-trap mechanism, whilst the young poles are used for construction purposes in traditional buildings. The wood is used as fuel.

Fuel: Usually wood, plant materials that have been mentioned as being a good fuel.

Tannin: An astringent substance obtaied from plants, it is used medicinally, as a dye and mordant, stabilizer in pesticide etc.

Wood: A list of the trees and shrubs that are noted for having useful wood.

How it is grown

A plant of the humid, lowland tropics, where it is found at elevations up to 500 metres. It grows best in areas where the mean annual temperature ranges between 22 - 28°c, but can succeed at 18 - 35°c. It prefers a mean annual rainfall in the range of 2,000 - 4,000mm, but tolerates from 1,500 - 5,000mm. Succeeds in full sun and in partial shade. Grows best in a fertile, moist but well-drained, medium to heavy soil with high humidity. Prefers a pH in the range 5.5 - 7, but can tolerate 5 - 7.5. A fast growing tree but the bole never reaches a great diameter. The species coppices well, producing strong, highly phototrophic shoots. The bark is harvested as the source of the alkaloid yohimbine. The main stem gives the best material but is not rich in alkaloids until the tree is 15 - 20 years of age, by which time it can contain 2 - 15% yohimbine. Bark exploitation is a seasonal activity as the yohimbine levels are highest during the rainy season. Although the trees callus well after a small amount of bark removal, removal of large quantities of bark can lead to an attack by a small stem borer which penetrates the unprotected stem, killing the tree.

Propagating it: Seed -

Best place to grow:

Habit: Tree

Hardiness: 10-12

Growth: Medium

Soil: Medium, heavy (clay)

Shade: Semi-shade, no shade

Moisture: Moist

Things to keep in mind

The bark contains alkaloids that have medical applications at low doses but are toxic at larger doses. Poisonous doses of the bark are reported to paralyze respiration and the drug can cause severe hypotension, abdominal distress and weakness. The bark can also be used as a fish poison

Its other names

Local names

Yohimbe, johimbe, yohimbe cortex, yohimbe tree, yohimbebaum, yohimbeh, yohimbehe cortex, yohimbeherinde, yohimbi, yohimbé.

Synonyms

Corynanthe johimbe K.Schum. Pausinystalia trillesii Beille Pausinystalia zenkeri W.Brandt