Catuaba is not a plant: what fourteen bottles in a Vienna laboratory turned out to contain

By the Jelly Force TeamLast updated September 20268 min readBotanical identity · Reviewed by Dr. Dean Tomlin

This is the least flattering article on this website about an ingredient that appears on the bottle it sells, and it is here because the finding is twenty years old, well documented and almost never mentioned in the aisle.

A word that does not name a plant

Most botanical names on a supplement label point at a species. Maca is Lepidium meyenii. Ashwagandha is Withania somnifera. Muira puama is Ptychopetalum olacoides, which is a different conversation but at least a settled one.

Catuaba points at a category. In Brazil the word is applied to barks from Anemopaegma, from Erythroxylum and from Trichilia, which belong to three unrelated plant families. They are traded under the same name, sold for the same purpose and, on a label, indistinguishable from one another.

That is not an accusation about any particular product. It is a fact about the vocabulary, and it is the reason a bottle naming catuaba is naming a tradition rather than a substance.

Fourteen bottles in a Vienna laboratory

In 2004 a group at the University of Vienna did the obvious experiment. They bought fourteen commercial catuaba preparations, each specified on its own label as bark of an Anemopaegma, Erythroxylum or Trichilia species, and examined every one for identity and purity (Kletter 2004).

The findings, in the paper's own order. Only a minority of the samples contained the crude drug their labels claimed. More than half were adulterated with different crude drugs. Thin-layer chromatographic fingerprints confirmed the heterogeneity. The majority of samples contained bark from Trichilia catigua, whatever their labels said. And in half the samples, tropane alkaloids were detected at varying concentrations.

The team then elucidated the structures of the two main alkaloids, catuabine D and its hydroxymethyl derivative, and published the analytical data so somebody else could repeat the work.

Read off the abstract of the 2004 Planta Medica paper, which is linked in the sources at the foot of this article.

The second finding, which nobody quotes

The identity result is the one that gets cited. The paper's last sentence is the one that matters more, and it is quoted here in full because paraphrasing it would soften it.

Neither aqueous nor methanolic extracts of the Trichilia catigua reference material, nor alkaloid-enriched fractions of the commercial samples, showed any effect on the rabbit corpus cavernosum in an in vitro test.

Corpus cavernosum is erectile tissue, and relaxing it is the mechanism every product in this category is implicitly invoking. The verified reference material did nothing to it. So did the alkaloid fractions from the commercial samples.

One in vitro assay is not the last word on an ingredient, and it would be wrong to present it as one. It is, however, the only direct test of this bark against this mechanism that exists in the literature, and it came back negative.

Twenty years later, the same sentence

A 2024 review in the Journal of Ethnopharmacology compiled seventy-four plant species used in Brazilian folk medicine for male sexual dysfunction, and identified the fourteen with pharmacological study behind them (Teixeira 2024).

Trichilia catigua is on that list of fourteen, which is worth noting: the bark that most commercial catuaba turns out to contain has been studied, and the review's proposed mechanisms include antioxidant activity, phosphodiesterase-5 inhibition and effects on dopaminergic and noradrenergic pathways.

And then, in the same paper: several different species popularly known as catuaba were identified, leading to adulterations and controversial effects. Two decades after the Vienna work, the sentence has not changed.

What it means for a bottle naming catuaba

Three things, and the first is the one to hold on to.

A reader cannot tell from the word which plant is in the bottle. That is a property of the ingredient name rather than of any manufacturer, and it applies identically to every product in this aisle that uses it.

The probability is that it is Trichilia catigua, since that is what the majority of commercial samples contained and it is the species the pharmacological literature has accumulated around. That is an inference from a twenty-year-old market survey rather than a fact about any particular bottle.

And the amount question that applies to every ingredient applies here with an extra layer. There is no established human amount for catuaba, because the work that would establish one has not been done, and it is hard to design when the material is not reliably identified.

There is a fourth thing, and it cuts the other way. The pharmacological literature that does exist has accumulated around Trichilia catigua, which is also what most commercial material turned out to be. So the likeliest content of a catuaba product is the species with the most work behind it, which is a more comfortable position than the identity problem on its own suggests. It remains an inference rather than a fact about any particular bottle, and inferences are what a reader is left with when a name does not identify a plant.

• The word identifies a trade category, not a species
• Most commercial material appears to be Trichilia catigua
• The one direct in vitro test of the reference bark came back negative
• No human amount is established, and identity is the reason
• None of this is specific to any one product on the shelf

Why the problem generalises past one bark

Catuaba is the clearest documented case, and it is not the only one of its kind. The general problem is that a botanical supply chain runs on common names, and common names are regional, overlapping and old.

Three things make a name unreliable. It can be shared by unrelated species, as catuaba is across three plant families. It can be applied to different plants in different regions of one country. And it can travel further than the plant does, so that a name arrives in an export market attached to whatever the nearest available substitute is.

The defence against all three is identity testing, which is not exotic. Microscopy, a chromatographic fingerprint or a DNA method will each establish what a batch of bark actually is, and none of them is expensive relative to the value of a consignment. A manufacturer that does it can say so; one that buys on a trade name cannot.

The reason it matters more in this category than in most is what the barks are being sold for. A traditional preparation used locally is bought from somebody who knows the plant. A capsule or a gummy sold internationally is bought from a document, and a document that says catuaba has said less than it appears to. The same 2019 work on traditional Amazonian preparations that screened for phosphodiesterase-5 inhibition also screened the samples for sildenafil and found none (Schmeda-Hirschmann 2019), which is the other half of the identity question and the more alarming one.

The question worth asking a manufacturer

If catuaba matters to a purchase, there is one question that produces a real answer: which species, and from which supplier?

A manufacturer that can answer it has done identity testing or holds a certificate of analysis from a supplier that did. A manufacturer that cannot is buying on a trade name, which is how the fourteen samples in Vienna came to be what they were.

This desk has asked and will record the answer here when there is one. Until then the honest position is the one printed on the ingredients page: catuaba on this label is a traditional inclusion with a botanical question attached, and the question is the interesting part.

It is also worth keeping the scale of this in proportion. Catuaba is one of nine names sharing an 82 milligram blend. Whatever species it is, there is not very much of it, which is the subject of a different article on this journal. Identity and amount are two separate questions, and this bottle has one of each.