I´m working on a study of iboga samples available in the market for harm reduction, in order to assess the potency and possible adulterations or mislabelings.

I came across this paper that describes a death resulting from a mislabeled iboga sample that was actually Yohimbe (Pausinystalia johimbe): https://sci-hub.ru/https...s/pii/S0379073816302663.

It seems Yohimbe has been involved in several other poisoning cases and deaths: https://sci-hub.ru/https...s/pii/S0379073821000256.

Then I came across this paper which shows Yohimbine is actually also present in some Iboga samples.

It made me start wondering about how much mislabeled iboga samples or iboga samples with genetics that have a higher yohimbine content may be a significant factor in some of the reported iboga deaths.

Just to be clear i´m not a doctor, and it is known that ibogaine itself does have some cardiac effects like prolonged QT interval, and some deaths have occurred with supposedly pure ibogaine, so this hypothesis of yohimbine being a contributing factor in some deaths/complications may be wrong.

Still, looking at the papers of iboga-related poisonings, there is often a poor descirption of the toxicology analytical method used, there is no mention if they would have looked for the presence of yohimbine. Also the toxicological description of both yohimbe poisoning and some iboga deaths seem to match up (and not point out to heart damage?), for example:

source 1



source 2


source 3


Any thoughts?

I believe pulmonary edema can be the result of heart failure. If the heart does not pump blood around powerfully enough, all the little vessels in the lungs can become congested and liquids present in the blood start leaking into the alveoli.

But both yohimbine and ibogaine can cause heart failure.

Yohimbine has recently been banned in the EU as an over-the-counter supplement, exactly for this reason.
I think this might indicate that yohimbine can be dangerous, even in relatively small amounts, because they could have just banned supplements that contain larger amounts of the substance.

It has been taken as an aphrodisiac, but also as a metabolism enhancer for weight loss.

If you want these metabolic effects, you should take larger quantities of it, but both it's application as an aphrodisiac and as a metabolic stimulant is apparently considered unsafe.

So i find it plausible that even when relatively small quantities of yohimbe are taken in conjunction with ibogaïne, this would increase the risk of heart failure significantly.

But iboga is something that interacts negatively with a lot of drugs. I think drug interactions may be responsible for a lot of iboga deaths, because people may simply not be aware of these interactions.

Grapefruit, not even a drug, interacts with iboga for instance. It slows down the metabolism of ibogaïne so you could overdose on ibogaïne if you take a high dose of it and drink a lot of grapefruit juice. Grapefruit juice also affects the metabolism of yohimbine.

If you have a sample of iboga that is high in yohimbine and you then also drink grapefruit juice, you may be in for a very unpleasant experience.