Subtotal $0.00
Shop Now
Yohimbine is the main active alkaloid in the bark of yohimbe (Pausinystalia johimbe), an evergreen tree native to central and western Africa. It blocks alpha-2 adrenergic receptors, which can increase the release of noradrenaline, the body’s fight-or-flight messenger, and that is why it shows up in fat burners and pre-workouts. The fat-loss evidence rests on two tiny trials, while the safety record includes rapid heartbeat, high blood pressure, seizures and heart attacks. This guide explains yohimbe versus yohimbine HCl, what studies found, yohimbine side effects and who should not use it.
Peptide Labs sells two stimulant formulas that list yohimbine or yohimbe, and we describe them below with their label warnings. This article is general information, not medical advice.
Key Takeaways
- Yohimbe is the tree bark; yohimbine HCl is the purified form of its main alkaloid.
- NCCIH says there is not enough evidence to judge yohimbe for any condition, including weight loss.
- Two small trials of 20 people each reported weight or body fat changes; neither settles the question.
- Reported harms include rapid or irregular heartbeat, high blood pressure, anxiety, seizures and heart attacks.
- In a test of 49 US yohimbe products, only 2 labels gave both an accurate amount and side effect information.
Yohimbe vs yohimbine HCl
Yohimbe bark extract is a botanical. It contains yohimbine along with related alkaloids such as rauwolscine (also called alpha-yohimbine) and corynanthine, in amounts that vary from product to product. Yohimbine hydrochloride (yohimbine HCl) is the purified salt of the single alkaloid, which lets a label state an exact amount. Some fat burners list yohimbine HCl, some list yohimbe bark extract, and some list rauwolscine or alpha yohimbine from Rauwolfia vomitoria root, a different plant.
Their legal status differs too. Yohimbine HCl has been sold in the US as a prescription medicine, but prescriptions are now rare and most manufacturers have stopped making the tablets; a September 2026 search of the NIH DailyMed label database found no current prescription tablet label. The National Center for Complementary and Integrative Health (NCCIH) notes that it is illegal to market an over-the-counter yohimbine product for erectile dysfunction without FDA approval, yet yohimbe and yohimbine remain common in products sold as dietary supplements. Health Canada classes yohimbine as a prescription drug, and NCCIH says yohimbe supplements have been restricted or banned in many countries because of inaccurate labeling and serious side effects.
Does yohimbine help with fat loss?
The theory is that blocking alpha-2 receptors raises noradrenaline activity and frees up stored fat. Human evidence is thin:
| Study | Who took part | What happened |
|---|---|---|
| Kucio et al., 1991 (Poland) | 20 women with obesity on a 1,000-calorie diet, 3 weeks | Lost 3.55 kg with yohimbine vs 2.21 kg with placebo; no measurable change in fat breakdown markers |
| Ostojic, 2006 (Serbia) | 20 professional male soccer players, 21 days | Body fat fell from 9.3% to 7.1%; no change in body weight, muscle mass or performance |
Both trials were tiny and short, and neither has been repeated at scale. The NIH Office of Dietary Supplements says yohimbe doesn’t help you lose weight and might not be safe, and NCCIH says there is not enough evidence to draw conclusions about weight loss, athletic performance or erectile dysfunction. In fat burners, yohimbine is almost always combined with caffeine and other stimulants, so any effect you feel is hard to attribute. Our guide on whether fat burners work reviews the pooled evidence, and our metabolism guide explains what actually changes energy use.
Yohimbine side effects
NCCIH says yohimbine has been associated with irregular heartbeat, blood pressure problems, heart attacks and seizures. In a comparison of calls to the California Poison Control System over seven years, yohimbe caused stomach problems, rapid heartbeat, anxiety and high blood pressure, and callers about yohimbe were more likely to need medical care than other callers. The Office of Dietary Supplements also lists headaches, heart failure and death among reported harms. Health Canada adds dizziness, tremors, nausea and sleep problems.
A 2006 poison center surveillance project run with the FDA found that yohimbe products accounted for 18% of symptomatic supplement cases, second only to caffeine products at 47%, and it recorded yohimbe taken together with bupropion and with methamphetamine. A 2009 case report described a 37-year-old bodybuilder who swallowed a very large amount of yohimbine at a competition and developed repeated seizures, a coma and a blood pressure of 259/107. He recovered after emergency care that included a breathing tube.
Drug interactions
NCCIH says not to use yohimbe if you take monoamine oxidase inhibitors (MAOIs) or tricyclic antidepressants. Because yohimbine raises heart rate and blood pressure, adding other stimulants stacks the load; the Lipo-6 label, for example, says not to combine it with coffee, tea, soda or other stimulant-containing supplements or medications. People taking blood pressure, psychiatric or prescription stimulant medicines should ask a pharmacist before using any yohimbine product.
Labels often do not match what is inside
A 2016 study led by Harvard researcher Pieter Cohen tested 49 brands labeled as containing yohimbe or yohimbine from seven major US retailers. Yohimbine per serving ranged from none detected to 12.1 mg. Only 11 brands (22%) listed a specific amount, and most of those were wrong, with actual content between 23% and 147% of the label. Nearly 4 in 10 lacked the other yohimbe alkaloids, suggesting a highly processed or synthetic source, 18% gave no side effect information, and only 2 of 49 combined an accurate amount with side effect warnings.
Proprietary blends add to the problem. When a label lists yohimbine inside a blend, you cannot tell how much you are getting, which is one more reason to check with a healthcare provider first.
Who should not use yohimbine
- Pregnant or breastfeeding people: NCCIH says it might be unsafe, and Health Canada says it should not be used.
- Children and teens: Health Canada says it should not be used by children, and the stimulant labels we carry exclude anyone under 18.
- People with high blood pressure, heart disease, kidney disease or liver disease: Health Canada warns of serious adverse reactions in these groups.
- People taking MAOIs or tricyclic antidepressants.
- Anyone scheduled for surgery: both products below say to stop 2 weeks before.
- Competitive athletes: the Lipo-6 label warns it may contain ingredients banned by some sports organizations.
Yohimbine products at Peptide Labs
Two products we carry list yohimbine or yohimbe. We describe them so you can read the labels closely, not as a recommendation; both are high-stimulant formulas for healthy adults only.
- Nutrex Lipo-6 Black Ultra Concentrate: yohimbine HCl and rauwolscine inside a 305 mg complex with caffeine, theobromine and theacrine; individual amounts are not disclosed. The label says to stop if you notice a rapid heartbeat, dizziness, severe headaches or shortness of breath, and excludes anyone under 18, pregnant or nursing.
- GAT Sport JetFuel Original: yohimbe bark extract inside a 961.74 mg proprietary blend with caffeine, guarana, bitter orange, green tea and 5-HTP. Caffeine is stated as about 200 mg per serving on the listing’s Supplement Facts image and about 286 mg on the brand’s page, so check your bottle.
InnoSupps Inno Shred GLP-1 lists 2 mg of alpha yohimbine with 250 mg of caffeine per serving. Compare labels in our fat burners category and count every source of caffeine you take. JetFuel also contains 5-HTP; our 5-HTP guide explains its drug interactions.
Frequently Asked Questions
What is yohimbine?
An alkaloid from the bark of the African yohimbe tree. It blocks alpha-2 adrenergic receptors and is added to some fat burners and pre-workout supplements.
What is the difference between yohimbe and yohimbine HCl?
Yohimbe is the bark extract, with yohimbine and related alkaloids in varying amounts. Yohimbine HCl is the purified single compound.
What are the most common yohimbine side effects?
Rapid heartbeat, high blood pressure, anxiety, stomach problems, headache, dizziness and sleep problems. Seizures and heart attacks have also been reported.
Does yohimbine help with fat loss?
Two small trials of 20 people each reported changes in weight or body fat. NCCIH says the evidence is not enough to draw conclusions, and ODS says yohimbe doesn’t help with weight loss.
Is yohimbine legal in the US?
Yohimbe and yohimbine are sold in US dietary supplements, but marketing an over-the-counter product for erectile dysfunction without FDA approval is illegal. Health Canada classes yohimbine as a prescription drug.
Can I take yohimbine with caffeine?
Most fat burners already combine them, and stacking stimulants raises heart rate and blood pressure. Follow the label warnings and ask a healthcare provider first.
Questions about a label? Contact us or read our Buyer’s Guide. Follow the label and ask a healthcare provider before starting any supplement, especially if you take medicines. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Last reviewed September 2026.
Related guides: Do Fat Burners Work? Thermogenic Ingredients, Evidence and Risks, How to Boost Metabolism: What Really Changes the Calories You Burn, How Much Caffeine Is Too Much? Daily Limits, Overdose Signs and Label Math, Bitter Orange (Citrus Aurantium): Evidence, Side Effects and Label Checks.