The Iboga Plant

Almost everything written about iboga in English is about what the plant contains. This section is about the plant.

That distinction matters more than it sounds, because several of the claims that circulate about iboga are botanical claims, and most of them are wrong.

What it is

Tabernanthe iboga Baill., in the family Apocynaceae, the same family as periwinkle and oleander. A shrub or small tree of up to four metres, repeatedly branched, with white latex in every part and a trunk that rarely exceeds ten centimetres across. Its fruit is a yellow to red berry, and its seeds are small and deeply indented.

The genus holds exactly two accepted species. The other, Tabernanthe elliptica, grows in the Congos and Angola, and the distinction matters because some of the alkaloid figures attributed to iboga in the literature were measured on it.

Where it actually grows

Kew records the native range as West Central Tropical Africa to Angola: Gabon, Cameroon, the Central African Republic, both Congos, and Angola with Cabinda. The IUCN’s range list agrees.

So the plant is Central African, not Gabonese. Gabon is where its range and its ritual use overlap most closely, and where most traded material originates, but those are different statements from where it grows.

It grows in the forest understorey, sometimes in riverine or swamp forest. On altitude the sources disagree, one giving thirty to six hundred metres and another sea level to fifteen hundred, and we have not been able to reconcile them. Its seeds are dispersed by elephants, which eat the fruit.

Why the root bark, and why that is destructive

The alkaloids are distributed unevenly. PROTA gives root bark at five to six per cent, roots at one to two and a half, stem bark at two, seed at one, and leaves at under one. Recent work found the leaves carry a different structural class altogether and no ibogaine at all.

So the material anyone wants is the root bark, and reaching it means digging. PROTA is direct about what that means in practice: in the wild, whole plants are uprooted, which destroys natural stands, while in home gardens only part of the roots is taken.

Partial harvest that the plant survives is documented. The method is described, and the plant does resprout from the trunk. What is missing is any measurement of how often it survives, or of how long recovery takes, and that gap is real rather than a failure of our searching.

Ibogaine is not the plant

About thirty alkaloids have been identified in the root bark by modern mass spectrometry. Ibogaine is the best known and not the whole story: ibogaline, iboxygaine, ibogamine, catharanthine, voacangine and coronaridine are all present.

How much of the mixture is ibogaine has two published answers that differ by a factor of three. A 2002 study estimated eighty per cent by looking at stained spots on a plate. A 2018 instrumental analysis put it at roughly a quarter of the alkaloid signal. Neither is a gravimetric assay, and quoting either alone is misleading.

What the plant is made of sets the chemistry out properly.

The plant is not the only source

A good deal of the ibogaine used commercially is not extracted from iboga at all. It is made from voacangine, taken from the bark of Voacanga africana, by hydrolysis and decarboxylation. What share of supply comes that way has never been measured, and where ibogaine actually comes from sets out why the honest answer is that nobody knows.

That route was patented in 1957, and the patent states the reason plainly: the bark can be gathered without destroying the plant, and the roots cannot. Ibogaine has also been synthesised outright since 1966, with a modular route published in 2025.

None of which has yet relieved the pressure on wild iboga. Where ibogaine actually comes from follows that thread, because it changes the conservation argument in ways the debate has not caught up with.

What nobody has measured

The species is listed by the IUCN as Least Concern, assessed in 2018 and published in 2019, on the reasoning that it has a wide distribution and a large population facing no major threat.

The assessment’s field for number of mature individuals is empty. So is the field for subpopulations, and the population description, and the threats table. The “large population” is asserted, not counted.

We say that not to attack the assessors, who were assessing thousands of trees, but because the status is quoted as though it settled something. It does not, and the plant remains outside every CITES appendix, which we verified against the Convention’s own checklist.

What this section covers

Tabernanthe iboga, the botanical profile covers naming, structure and chemistry. Growing iboga from seed covers germination and cultivation, including the commercial plantations that already exist. Where ibogaine comes from covers Voacanga, synthesis, and a widely repeated claim about an Amazonian species that does not survive checking. The other alkaloids of iboga covers everything in the plant that is not ibogaine, including the one that is more potent than ibogaine at the receptor the field cares about.