Bark of a West African tree containing the alkaloid yohimbine, an alpha-2 adrenergic antagonist. Prescription yohimbine hydrochloride is a defined drug; yohimbe bark supplements are not.
This is the most acutely dangerous product in the catalogue. Yohimbine raises blood pressure and heart rate, and poison centre data document seizures, arrhythmias, kidney failure and deaths. Analyses of retail yohimbe supplements have found alkaloid content ranging from almost none to more than twice the label claim, so nobody taking it knows their dose of a drug with a narrow margin between an effect and a hypertensive emergency.
Labels state yohimbine content that independent testing frequently contradicts — a product without this marker may not resemble what was studied.
Also known as
Yohimbine, Yohimbe bark, Johimbe
Regulation: Banned as a food supplement ingredient in several European countries and restricted in Australia and Canada. Prescription yohimbine hydrochloride exists in some countries for erectile dysfunction. In the US, yohimbe is sold over the counter, and the FDA has warned about products with undisclosed or misstated alkaloid content — the same regulatory gap that allowed ephedra to remain on shelves until it was banned after deaths.
What the research used
The amounts, forms and durations published trials of Yohimbe actually administered.
These are the amounts published trials administered — not a recommendation, and not a dose to copy. Trial participants were screened, supervised and given a characterised preparation. What is in a retail bottle is frequently not what was studied, and the amount that suits one person is not general advice.
Studied for Erectile dysfunction, with prescription yohimbine hydrochloride
These trials used a pharmaceutical-grade compound under medical supervision. Bark supplements deliver an unknown and highly variable amount of the same alkaloid, which is not the same thing.
Studied for Body fat loss
0.2 mg/kg
Not enough
Yohimbine hydrochloride, divided doses · 3 weeks
From one very small trial in athletes. It is routinely cited to sell fat-burner products whose cardiovascular risk was never weighed against that result.
This is general information about food, not medical advice. It cannot diagnose, treat or replace guidance from a clinician who knows your history.
When it was taken
Each window says whether a trial compared it against an alternative, or whether it is convention and pharmacology. Most timing advice is the second kind.
None of the timings below were directly compared in a trial. They reflect how the research happened to dose, or what the pharmacology implies — which is not the same as a timing being better.
⏳On an empty stomach
Not enough
Fat-loss protocols dose it fasted before exercise on the reasoning that insulin blunts lipolysis. This compounds the cardiovascular stimulation rather than being a tested safety practice.
Timing was not directly compared. This reflects convention or how the compound behaves in the body, not a trial showing this window works better.
The evidence in depth
Best supported: Limited
What each association actually rests on, and the papers behind it. A rating describes the state of the research, not how promising the supplement sounds. How we rate evidence.
Trials of prescription yohimbine hydrochloride report modest improvement in erectile function compared with placebo. That evidence concerns a measured pharmaceutical dose under supervision, not bark supplements whose alkaloid content is unpredictable.
What may be going on: Yohimbine blocks alpha-2 adrenergic receptors, increasing noradrenaline release — which is also the source of its cardiovascular toxicity.
Limited evidence. Early human work, or mostly lab and animal research.
Evidence is limited for yohimbine and fat loss. One very small trial in athletes underpins a large market, and the cardiovascular risks are documented far better than the benefit.
Not enough evidence. Not enough human research to say anything useful yet.
Deep research mode adds each paper’s own conclusion and stated limitations.
Things to know
Interactions, contraindications and dose limits, most serious first. Concentrated extracts interact with medication in ways the whole plant does not, so this section carries more weight here than it does on a food page.
Worth knowing
Serious cardiovascular events and deaths
Poison centre and case series data document severe hypertension, tachycardia, arrhythmia, chest pain, seizures, kidney failure and deaths associated with yohimbe. Symptoms can appear at doses within the range products supply.
Worth knowing
Alkaloid content bears little relation to the label
Independent analysis of retail yohimbe products found yohimbine content ranging from undetectable to more than double the stated amount, with many failing to state it at all. Dosing a narrow-margin drug from such a product is not possible.
Combining yohimbine with MAO inhibitors can precipitate a hypertensive crisis. It also interacts with tricyclic antidepressants, stimulants including caffeine and amphetamines, and blood pressure medication whose effect it opposes.
Avoid
Heart disease, hypertension, kidney and liver disease, anxiety disorders
Yohimbe is contraindicated in cardiovascular disease, uncontrolled hypertension, kidney or liver impairment, and anxiety or panic disorder, where it reliably provokes symptoms. It is also used experimentally to induce panic, which tells you what to expect.
Avoid
Pregnancy and breastfeeding
Yohimbe should never be used in pregnancy or breastfeeding, and it should be stopped well before any procedure requiring anaesthesia.