Yohimbine
Summary
Yohimbine is the main alkaloid in yohimbe bark and a prescription drug in some countries. Small, mostly old trials of prescription yohimbine HCl found more erectile improvement than placebo; fat-loss trials are tiny and mixed. It is absorbed and cleared fast but very unevenly between people, and poison-centre reports link supplements to fast heartbeat, anxiety and high blood pressure.
Key facts
- Associated with irregular heartbeat, blood-pressure problems, heart attacks and seizures; restricted or banned in many countries[10]
- In CYP2D6 poor metabolisers, a 5 mg dose gave about 126 times the blood exposure (AUC 2,044 vs 16.2 ng·h/mL) and a 6.6 h vs 0.64 h half-life compared with extensive metabolisers[18]
- Oral bioavailability ranged from 7% to 87% (mean 33%) in 7 men; a later study measured 22.3 ± 21.5%[6][16]
- After 10 mg by mouth: absorption half-time 0.17 h (about 10 minutes) and elimination half-life 0.60 ± 0.26 h in 8 men[13]
- 238 California cases (2000-2006): stomach upset 46%, fast heartbeat 43%, anxiety or agitation 33%, high blood pressure 25%; 98.7% involved supplement products[8]
- Of 49 US supplements, only 11 listed a yohimbine amount and most of those were wrong (23% to 147% of the label); content ranged from none to 12.1 mg per serving[7]
- Meta-analysis of 8 RCTs of prescription yohimbine HCl for erectile dysfunction: pooled odds of erectile improvement 2.87 times placebo (7 trials reported this outcome); yohimbine alone OR 2.08[2]
- Three small trials: more weight loss on a diet (n=20, 3 weeks), lower body fat in soccer players (n=20, 21 days), and no effect on weight or body fat over 6 months (n=33)[21][3][22]
- Not for people on MAO-inhibitor or tricyclic antidepressants (NIH fact sheet); a case of brain haemorrhage occurred in a woman on clonidine[10][9]
- 5 graded human outcomes on this page
- October 13, 2026
How it works
EstablishedYohimbine blocks alpha-2 adrenergic receptors, which normally brake noradrenaline release, so sympathetic output rises: noradrenaline, heart rate and blood pressure go up. Fat cells also carry alpha-2 receptors that restrain fat breakdown, which is the rationale for fat-loss use. Its main metabolite, 11-hydroxy-yohimbine, also blocks alpha-2 receptors in human cell tests.[11][14][17][4][20][28]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
At a glance: strongest evidence per outcome
| Outcome | Grade | Effect | Strongest evidence | Rows |
|---|---|---|---|---|
| Erectile function | Grade C | Improved | Meta-analysis of 8 trials · n = 460 · 2021 | 1 row |
| Body weight & fat | Grade D | No effect | RCT · n = 33 · 1991 | 3 rows |
| Exercise performance | Grade D | Improved | Crossover RCT · n = 18 · 2022 | 1 row |
Every graded row
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Erectile function in men with erectile dysfunction | Improved | Grade C | Meta-analysis · n = 460 · 2021 Men aged 18-73 with erectile dysfunction of mixed causes in 8 double-blind RCTs (1987-2010) Form: Prescription yohimbine HCl alone or combined with L-arginine or trazodone · Dose: Mostly 5.4-6 mg three or four times daily; one trial used 100 mg/day · Duration: 2-10 weeks Erectile improvement was more likely than with placebo (OR 2.87, 95% CI 1.94-4.25); yohimbine alone OR 2.08. Overall sexual function did not differ significantly with yohimbine alone (P = .07). | 35118966 (opens PubMed)Source [2] |
| Body weight, body fat and fat distribution in men | No effect | Grade D | RCT · n = 33 · 1991 Men, mean age 42 (USA); 47 randomised, 33 completed Form: Yohimbine · Dose: High dose, titrated to a peak of 43 mg/day · Duration: 6 months No effect versus placebo on body weight, BMI, total or HDL cholesterol, body fat, waist-to-hip ratio or CT-measured fat distribution. | 1960007 (opens PubMed)Source [22] |
| Weight loss on a low-calorie diet in women with obesity | Improved | Grade D | RCT · n = 20 · 1991 Female outpatients with obesity (Poland), after a 3-week 1,000 kcal/day run-in diet Form: Yohimbine tablets · Dose: 5 mg four times daily (20 mg/day) · Duration: 3 weeks (with a 1,000 kcal/day diet) Weight loss was 3.55 ± 0.24 kg with yohimbine vs 2.21 ± 0.37 kg with placebo (P < 0.005). Serum glycerol, the lipolysis marker, did not change significantly. | 1955308 (opens PubMed)Source [21] |
| Body fat in professional soccer players | Improved | Grade D | RCT · n = 20 · 2006 Elite male soccer players in Serbia Form: Yohimbine tablets · Dose: 20 mg/day in two doses · Duration: 21 days Body fat fell from 9.3% to 7.1% with yohimbine; body mass, muscle mass and all performance tests did not change. No side effects were reported. | 17214405 (opens PubMed)Source [3] |
| Repeated sprint power in active women | Improved | Grade D | Crossover RCT · n = 18 · 2022 Physically active women (USA) Form: Yohimbine HCl · Dose: 2.5 mg single dose 20 min before exercise · Duration: Single session Mean power and total work over 3 x 15 s Wingate sprints were higher and fatigue index and lactate lower than placebo; adrenaline and heart rate rose. | 35162339 (opens PubMed)Source [4] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Yohimbine HCl (prescription and supplement tablets) | Varies[6] | Absorbed fast (absorption half-time 0.17 h after 10 mg) and usually cleared fast (half-life about 0.6 h), but oral bioavailability ranged from 7% to 87% (mean 33%). A high-fat meal reduced both the rate and extent of absorption.[13][6][19] | Side effects reported to poison centres: stomach upset, fast heartbeat, anxiety, high blood pressure. 5.4 mg yohimbine HCl contains about 4.9 mg yohimbine base.[8][38] | Erectile dysfunction trials (about 15–22 mg/day), fat-loss trials (20–43 mg/day) and small sports studies (2.5–20 mg/day) |
| Yohimbe bark extract | Varies[7] | No human pharmacokinetic data for bark extracts; analysed products ranged from no detectable yohimbine to 12.1 mg per serving.[7] | Label amounts are unreliable, so the actual dose is often unknown.[7][10] | Not tested in controlled human trials |
| Rauwolscine (alpha-yohimbine) | Varies[37] | A stereoisomer of yohimbine (same formula, different 3D shape), not the same molecule. We found no human pharmacokinetic studies.[37] | Not characterised in controlled human studies; it is one of the alkaloids measured in yohimbe products.[7][37] | No controlled human supplement trials found (PubMed search, October 2026) |
Studied doses
Doses studied in human trials ranged from a single 2.5 mg dose before exercise to 20 mg/day in the short fat-loss trials (5 mg four times daily, or 10 mg twice daily) and about 15–22 mg/day of prescription yohimbine HCl in most erectile dysfunction trials. Single oral doses up to 21.6 mg were given in pharmacology studies, a 6-day safety study went up to 16.2 mg three times daily, a 6-month trial titrated up to 43 mg/day, and one erectile trial used 100 mg/day. A lipolysis study dosed by body weight (0.2 mg/kg, about 14 mg at 70 kg). These are doses researchers used, not targets, and the same dose produced very different blood levels in different people.[4][21][3][2][19][15][22][20][18]
How long trials ran before effects were measured
When each outcome was assessed in the cited trials. It is not a promise of when anyone will notice a change.
- Within about 20–25 minutes in most people · Absorption half-time 0.17 h after 10 mg; time to peak 0.36 h in CYP2D6 extensive metabolisers but about 1.4 h in poor metabolisers after 5 mg[13][18]
- Within 15 minutes (intravenous) · Plasma noradrenaline tripled within 15 minutes of 0.25–0.5 mg/kg intravenously[14]
- Measured at 60 minutes · Standing diastolic pressure up 11 mm Hg 60 minutes after 5.4 mg[5]
- Dose given 20 minutes before exercise · Single 2.5 mg dose before 3 × 15 s sprints[4]
- 3 weeks in two small trials; no effect at 6 months · Diet trial in women and soccer-player trial at 20 mg/day; 6-month trial in men up to 43 mg/day[21][3][22]
- 2–10 weeks · Trial lengths in the 2021 meta-analysis[2]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
Medicines
- MAO-inhibitor and tricyclic antidepressantsNIH fact sheetThe NIH fact sheet says not to use yohimbe with these antidepressants because of interactions.[10]
- SSRIs and other CYP2D6 inhibitorsPK studyYohimbine is cleared mainly by CYP2D6 (an estimated 99.5% of clearance in a 2020 trial). Paroxetine 20 mg cut yohimbine clearance more than fivefold in extensive metabolisers; other strong CYP2D6 inhibitors would be expected to act similarly (inferred). The Yocon label says it should not be combined with antidepressants or other mood-modifying drugs.[18][31]
- Clonidine and other centrally acting blood-pressure drugsCase reportA woman on long-term clonidine (also taking bupropion and desvenlafaxine) had blood pressure of 198/93 and a basal-ganglia haemorrhage after a yohimbine-labelled supplement; authors note clonidine use may amplify yohimbine effects.[9]
- Blood-pressure-lowering medicinesRCTYohimbine raises blood pressure: 10 mg raised diastolic pressure in people with untreated hypertension but not in healthy volunteers, 5.4 mg raised standing diastolic pressure by 11 mm Hg in autonomic failure, and high blood pressure was reported in 25% of poison-centre cases.[29][5][8]
- Caffeine, pre-workouts and other stimulantsReviewNo controlled trial has tested yohimbine with caffeine; a 2002 hypothesis paper only proposed that the pairing be studied. Stimulant supplements including yohimbine are linked to tachycardia, hypertension and cardiac events, and in the haemorrhage case the authors suggest bupropion and desvenlafaxine likely worsened the reaction.[30][12][9]
Who should be careful
- Heart disease, high blood pressure or arrhythmia
- Yohimbine has been associated with irregular heartbeat, blood-pressure problems, heart attacks and seizures, and raised diastolic pressure in people with untreated hypertension.[10][32][29]
- Panic disorder, PTSD and anxiety
- Researchers use yohimbine to provoke anxiety: it triggered panic attacks in 37 of 68 people with panic disorder or agoraphobia with panic attacks (1 of 20 healthy volunteers), and intravenous yohimbine triggered panic attacks in 14 of 20 men with PTSD.[23][24]
- Other psychiatric conditions
- The Yocon prescribing information says it is not intended for psychiatric patients in general or for use with mood-modifying drugs.[31]
- Kidney or liver disease
- Kidney disease is the listed contraindication on the Yocon label, and Health Canada warns of serious reactions in people with kidney or liver disease. Yohimbine is cleared mainly by liver metabolism.[31][32][13]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Safety first
The risks are better documented than the benefits.
- Poison-centre reports
- California poison centre cases rose from 1.8 to 8.0 per 10,000 adult exposures between 2000 and 2006, and yohimbine cases were more likely to have severe outcomes (OR 5.81) than average exposures.[8]
- Labels you cannot trust
- Only 2 of 49 US products gave both an accurate yohimbine amount and side-effect information.[7]
- Legal status
- US: selling an over-the-counter yohimbine product as an erectile dysfunction remedy without FDA approval is illegal. Canada: yohimbine and its salts are on the Prescription Drug List. Australia: yohimbine is prescription-only. EU: yohimbe bark and its preparations have been prohibited in food since 2019. UK: herbal medicines containing yohimbe bark may be sold only in registered pharmacies.[10][33][34][35][36]
How the body handles yohimbine
Fast in, fast out for most people, with large exceptions.
- Absorption and half-life
- After a single 10 mg oral dose in 8 men, the absorption half-time was 0.17 ± 0.11 h and the elimination half-life 0.60 ± 0.26 h; almost none (0.35%) left unchanged in urine, so clearance is by metabolism.[13]
- Bioavailability
- With 10 mg oral vs intravenous doses in 7 men, oral bioavailability ranged from 7% to 87% (mean 33%); a later study found 22.3 ± 21.5%. The authors note dosing may need individualising.[6][16]
- Intravenous data
- After 0.25–0.5 mg/kg intravenously in 13 men, elimination half-life ranged from 0.25 to 2.5 h and plasma noradrenaline tripled within 15 minutes, while adrenaline did not change.[14]
- Repeated dosing
- Over 6 days at 5.4–16.2 mg three times daily or 21.6 mg twice daily (32 volunteers), there was no drug accumulation but large differences within and between people; catecholamines rose with blood levels.[15]
- Active metabolite
- The main metabolite, 11-hydroxy-yohimbine, blocks alpha-2 receptors in human cell tests and has a terminal half-life almost four times that of yohimbine (347 vs 91 minutes after intravenous dosing).[28][16]
- CYP2D6 genetics
- In 172 people, conversion to 11-hydroxy-yohimbine varied more than 1,000-fold and 17 showed none, with CYP2D6 the likely main route. In a 2020 trial, poor metabolisers had about 126 times the exposure of extensive metabolisers after 5 mg; about 10% of people of European ancestry are poor metabolisers.[17][18]
Fasted or with food?
Food appears to trade a softer peak for less fat mobilisation.
- Food slows absorption
- In single-dose studies up to 21.6 mg, a high-fat meal reduced both the rate and the extent of yohimbine absorption. The abstract gives no percentage, and we found no published figure for how much.[19]
- Food cancels the fat-mobilising effect
- 0.2 mg/kg by mouth raised blood glycerol and free fatty acids in fasting men; the effect was stronger during exercise and completely suppressed after a meal.[20]
Pre-workout and fasted cardio
An anecdotal community practice that has not been tested for fat loss.
Serious reactions on record
- Common complaints
- Health Canada lists anxiety and frequent urination as the most consistent side effects, plus dizziness, stomach upset, headache, sweating, insomnia, tremor, palpitations and severe hypertension; the Yocon label adds irritability.[32][31]
- Priapism
- A man needed surgery (a cavernosal shunt) for a prolonged erection after a yohimbe extract product.[25]
- Brain haemorrhage
- A 39-year-old woman on clonidine had blood pressure of 198/93 and a basal-ganglia haemorrhage after a yohimbine-labelled supplement; product content was not tested.[9]
- Deaths
- Two US medical examiner cases attributed death to acute yohimbine intoxication, with blood levels of 7,400 and 5,400 ng/mL.[27]
How to read the label
- Yohimbine vs yohimbeTrials used measured yohimbine HCl; many products list only yohimbe bark, with no yohimbine amount.[7][2]
- Label errorsWhere a yohimbine amount was listed, actual content ranged from 23% to 147% of the label.[7]
- Bark extract is not a yohimbine amountA bark-extract weight on the label says nothing about yohimbine content; analysed products ranged from none detected to 12.1 mg of yohimbine per serving.[7]
- Rauwolscine and alpha-yohimbineThese names refer to a stereoisomer of yohimbine, a different compound; we found no controlled human trials of it, and yohimbine data do not transfer to it.[37]
- Salt vs basePrescription tablets state yohimbine hydrochloride; about 90.7% of that weight is yohimbine itself (354.4 ÷ 390.9).[38][31]
Frequently asked questions
Is yohimbine the same as yohimbe or rauwolscine?
No. Yohimbine is one alkaloid in yohimbe bark, and bark products often do not say how much they contain. Rauwolscine (alpha-yohimbine) is a stereoisomer of yohimbine, a different compound with no controlled human trials.[7][10][37]
Does yohimbine work for erectile dysfunction?
Older trials of prescription yohimbine HCl found erectile improvement more often than placebo, but the trials were small and mostly decades old.[2]
Does yohimbine burn fat?
Evidence is thin and mixed. Two 3-week trials of 20 people found more weight loss on a diet or lower body fat with 20 mg/day; a 6-month trial in 33 men up to 43 mg/day found no effect on weight or body fat.[21][3][22]
Does food change how yohimbine works?
Yes. A high-fat meal slowed and reduced absorption, and a meal completely suppressed the rise in blood fat markers seen when fasting. Food may soften the peak, but it also seems to remove the effect people use it for. No study gives a precise percentage.[19][20]
Is yohimbine before fasted cardio evidence-based?
No. It is an anecdotal community practice built on a 1988 study of blood fat markers and a 2002 hypothesis paper; no trial has measured fat loss from that routine. Adding caffeine or other stimulants has not been tested, and stimulant supplements including yohimbine are linked to fast heartbeat and high blood pressure.[20][30][12]
Why do people react so differently to the same dose?
Absorption varies from 7% to 87%, and CYP2D6 genes control clearance: poor metabolisers had about 126 times the exposure after 5 mg. CYP2D6-blocking drugs such as paroxetine have a similar effect.[6][18]
What are the main side effects?
Stomach upset, fast heartbeat, anxiety or agitation and high blood pressure were the most common problems reported to a poison centre. Insomnia, tremor and frequent urination are also reported, and it can trigger panic attacks in people with panic disorder or PTSD.[8][32][23][24]
Is yohimbine legal?
It depends on the country. Yohimbine is prescription-only in Canada and Australia, yohimbe is prohibited in food in the EU, and in the UK herbal yohimbe medicines are pharmacy-only. In the US yohimbe is sold as a supplement, but not legally as an erectile dysfunction remedy without FDA approval.[33][34][35][36][10]
Sources
- [1]Yohimbine for erectile dysfunction: a systematic review and meta-analysis of randomized clinical trials.. J Urol, 1998. meta-analysis
- [2]Yohimbine as a treatment for erectile dysfunction: A systematic review and meta-analysis.. Turk J Urol, 2021. meta-analysis
- [3]Yohimbine: the effects on body composition and exercise performance in soccer players.. Res Sports Med, 2006. RCT
- [4]Effects of Acute Yohimbine Hydrochloride Supplementation on Repeated Supramaximal Sprint Performance.. Int J Environ Res Public Health, 2022. crossover-RCT
- [5]Comparative efficacy of yohimbine against pyridostigmine for the treatment of orthostatic hypotension in autonomic failure.. Hypertension, 2010. crossover-RCT
- [6]Yohimbine bioavailability in humans.. Eur J Clin Pharmacol, 1990. PK-study
- [7]Pharmaceutical quantities of yohimbine found in dietary supplements in the USA.. Drug Test Anal, 2016. observational
- [8]Adverse drug events associated with yohimbine-containing products: a retrospective review of the California Poison Control System reported cases.. Ann Pharmacother, 2010. observational
- [9]Intracranial hemorrhage after a single dose of Yohimbine in a chronic user of clonidine.. Am J Emerg Med, 2022. observational
- [10]Yohimbe: Usefulness and Safety. National Center for Complementary and Integrative Health (NIH), 2025. fact-sheet
- [11]Multifaced Nature of Yohimbine-A Promising Therapeutic Potential or a Risk?. Int J Mol Sci, 2024. review
- [12]Cardiovascular toxicity associated with supplement use.. Clin Toxicol (Phila), 2025. review
- [13]The pharmacokinetics of yohimbine in man.. Eur J Clin Pharmacol, 1987. PK-study
- [14]Yohimbine pharmacokinetics and interaction with the sympathetic nervous system in normal volunteers.. Eur J Clin Pharmacol, 1992. PK-study
- [15]Yohimbine elimination in normal volunteers is characterized by both one- and two-compartment behavior.. J Cardiovasc Pharmacol, 1997. PK-study
- [16]Biopharmaceutics and metabolism of yohimbine in humans.. Eur J Pharm Sci, 1999. PK-study
- [17]Human sympathetic activation by alpha2-adrenergic blockade with yohimbine: Bimodal, epistatic influence of cytochrome P450-mediated drug metabolism.. Clin Pharmacol Ther, 2004. PK-study
- [18]Oral Yohimbine as a New Probe Drug to Predict CYP2D6 Activity: Results of a Fixed-Sequence Phase I Trial.. Clin Pharmacokinet, 2020. PK-study
- [19]Effects of yohimbine on autonomic measures are determined by individual values for area under the concentration-time curve.. J Clin Pharmacol, 1996. PK-study
- [20]Alpha 2-antagonist compounds and lipid mobilization: evidence for a lipid mobilizing effect of oral yohimbine in healthy male volunteers.. Eur J Clin Invest, 1988. RCT
- [21]Does yohimbine act as a slimming drug?. Isr J Med Sci, 1991. RCT
- [22]Yohimbine does not affect fat distribution in men.. Int J Obes, 1991. RCT
- [23]Neurobiological mechanisms of panic anxiety: biochemical and behavioral correlates of yohimbine-induced panic attacks.. Am J Psychiatry, 1987. observational
- [24]Abnormal noradrenergic function in posttraumatic stress disorder.. Arch Gen Psychiatry, 1993. observational
- [25]Refractory priapism associated with ingestion of yohimbe extract.. J Med Toxicol, 2009. observational
- [26]CYP2D6 phenotype explains reported yohimbine concentrations in four severe acute intoxications.. Arch Toxicol, 2021. observational
- [27]Case study: two fatal case reports of acute yohimbine intoxication.. J Anal Toxicol, 2013. observational
- [28]Alpha 2-adrenoceptor antagonist potencies of two hydroxylated metabolites of yohimbine.. Br J Pharmacol (laboratory study in human platelets and fat cells), 1993. animal-study
- [29]Yohimbine effects on blood pressure and plasma catecholamines in human hypertension.. Am J Hypertens, 1995. RCT
- [30]Pre-exercise administration of yohimbine may enhance the efficacy of exercise training as a fat loss strategy by boosting lipolysis.. Med Hypotheses, 2002. review
- [31]Yocon (yohimbine hydrochloride) 5.4 mg tablets: prescribing information. Glenwood LLC, reproduced by RxList, 2008. label
- [32]Health Canada advises consumers not to use unapproved products containing yohimbine or yohimbe bark including Strauss Energy SIX capsules. Health Canada, 2006. safety-communication
- [33]Natural Health Products Ingredients Database: Yohimbine (non-NHP, listed in the Prescription Drug List). Health Canada, 2019. database
- [34]Erec-Bull tablets: safety advisory (undeclared yohimbine, a prescription-only substance in Australia). Therapeutic Goods Administration (Australia), 2014. safety-communication
- [35]Commission Regulation (EU) 2019/650 amending Annex III to Regulation (EC) No 1925/2006 as regards Yohimbe (Pausinystalia yohimbe). European Commission (Official Journal L 110), 2019. guideline
- [36]Banned and restricted herbal ingredients. Medicines and Healthcare products Regulatory Agency (UK), 2014. guideline
- [37]Rauwolscine (alpha-yohimbine), CID 643606. PubChem (NCBI), 2026. database
- [38]Yohimbine hydrochloride, CID 6169 (molecular weight 390.9) and yohimbine, CID 8969 (354.4). PubChem (NCBI), 2026. database
What changed
- Initial editorial evidence review: source titles and years taken from NCBI E-utilities esummary (no retraction or expression-of-concern flags), every evidence row, dose, n and duration read against the PubMed abstract or full text, funding and author affiliations checked where available, and grades held conservative.
- Editorial evidence re-review: added pharmacokinetics (Owen 1987, Guthrie 1990, Hedner 1992, Sturgill 1997, Le Corre 1999 and 2004, Vay 2020), fasted vs fed (Grasing 1996, Galitzky 1988), two fat-loss trials (Kucio 1991, Sax 1991), panic and PTSD challenge data, priapism and fatal-case reports, CYP2D6 and stimulant interactions, rauwolscine, and verified regulatory status for the US, Canada, Australia, EU and UK. Every PMID checked via NCBI esummary and key numbers read against abstracts or full text; grades held conservative.
- Independent adversarial re-check: every PMID re-verified via NCBI esummary (titles and years match, no retraction flags), numbers re-read against abstracts and the 2020 CYP2D6 trial's tables, and regulatory pages re-opened. Softened the 2021 intoxication wording to match the paper (same dose assumed; CYP2D6 could explain the spread), labelled pre-workout use as anecdotal, removed an unsourced drug example from the stimulant interaction, and noted that the 1993 metabolite study used human cells in the lab.