Yohimbine is an alkaloid extracted from the bark of the Pausinystalia yohimbe tree, native to Central and West Africa. For centuries, traditional African medicine has used yohimbe bark as an aphrodisiac and stimulant. The active compound, yohimbine, was isolated in the early 20th century and has since been studied for its effects on sexual function, body composition, and anxiety disorders.

What makes yohimbine unusual among herbal supplements is that it’s actually available as a prescription medication in several countries, including the UK and Australia. The prescription form (yohimbine hydrochloride) has been used since the 1980s to treat erectile dysfunction, though it’s largely been superseded by PDE5 inhibitors like sildenafil (Viagra). Over-the-counter yohimbe bark supplements remain popular, particularly in the bodybuilding community, though the actual yohimbine content in these products varies wildly.

How Does Yohimbine Work?

Yohimbine primarily acts as an alpha-2 adrenergic receptor antagonist. In plain English, it blocks certain receptors that normally inhibit the release of noradrenaline (norepinephrine). When these receptors are blocked, noradrenaline levels increase, which can lead to:

Increased heart rate and blood pressure
Enhanced fat breakdown (lipolysis), particularly in stubborn fat areas
Improved blood flow to erectile tissue
Heightened arousal and anxiety

This mechanism explains both its potential benefits and its significant side effect profile. The same pharmacological action that might help with erectile dysfunction or fat loss can also cause uncomfortable or dangerous cardiovascular effects.

1. Yohimbine and Erectile Dysfunction

Erectile dysfunction (ED) affects approximately 40% of men by age 40, with prevalence increasing with age 1. Before modern medications like sildenafil became available, yohimbine was one of the few options for treating ED.

What the Research Shows

A 2022 systematic review and meta-analysis examined eight randomised controlled trials involving 1,033 men with erectile dysfunction 2. The analysis found that yohimbine, alone and in combination with other supplements, showed improvements in erectile and sexual function compared to placebo.

However, there’s an important caveat: when the researchers looked at yohimbine alone (without combination products), the improvement in sexual function was not statistically significant. This suggests yohimbine may work better as an adjunct to other treatments rather than as a standalone therapy.

An older meta-analysis from 1998 reviewed seven placebo-controlled trials and found yohimbine superior to placebo for erectile dysfunction 3. But even the authors noted that the trials were of limited quality and the effect size was modest.

My honest assessment: Yohimbine might offer some benefit for mild erectile dysfunction, but I wouldn’t expect dramatic results. Modern PDE5 inhibitors like sildenafil are far more effective and better studied. If you’re considering yohimbine for ED, it’s worth discussing with a urologist who can assess whether it’s appropriate for your situation. For those looking for natural approaches to male sexual health, ginseng and tongkat ali have also been studied, though evidence remains limited.

2. Yohimbine and Fat Loss

This is where yohimbine gets most of its attention in the fitness community. The theory is straightforward: by blocking alpha-2 receptors, yohimbine should enhance fat burning, particularly in areas with high alpha-2 receptor density (commonly called “stubborn fat” - think lower abdomen, hips, and thighs).

What the Research Shows

A 2006 study in 20 professional football players found that taking 20 mg of yohimbine daily for 21 days reduced body fat percentage from 9.3% to 7.1%, while the placebo group showed no change 4. Importantly, there was no difference in weight, muscle mass, or athletic performance between groups - only body fat changed.

However, a longer six-month study in 37 adult men found no significant differences in weight, body mass index, body fat percentage, or total cholesterol between yohimbine and placebo groups 5. This was a more realistic scenario: sedentary men hoping yohimbine alone would help them lose weight.

The catch: The positive results appear to come primarily from studies combining yohimbine with exercise or caloric restriction. On its own, without other interventions, yohimbine doesn’t seem to produce meaningful fat loss. The football player study worked because elite athletes were already training intensively. For the average person sitting at a desk, popping yohimbine supplements probably won’t make a noticeable difference.

There’s also the insulin issue. Research suggests that elevated insulin levels blunt yohimbine’s fat-burning effects 6. This is why some fitness enthusiasts take yohimbine in a fasted state or on very low-carbohydrate diets. Whether this actually translates to better real-world results remains unclear.

Worth noting: If you’re looking for supplements to support weight management, caffeine has a much stronger evidence base and is considerably safer. For those struggling with weight, addressing the underlying causes - diet quality, physical activity, sleep, and stress - will always be more effective than any supplement.

3. Yohimbine and Specific Phobias

This is a less well-known area of yohimbine research but potentially interesting for mental health applications.

Exposure therapy is the gold standard treatment for phobias - gradually exposing someone to their fear in a controlled setting until the fear response diminishes. Researchers have explored whether yohimbine might enhance the effectiveness of exposure therapy by increasing noradrenaline levels during the exposure sessions.

What the Research Shows

A 2009 study in 20 people with claustrophobia found that yohimbine (approximately 10.8 mg) taken before virtual reality exposure therapy sessions improved outcomes compared to placebo 7. Participants who received yohimbine showed greater reductions in claustrophobic fear.

However, a larger 2011 study in 76 people with fear of flying found no benefit from yohimbine when combined with virtual reality exposure therapy 8. The researchers speculated that yohimbine might work better for some types of phobias than others, or that the virtual reality setup wasn’t sufficiently realistic.

My take: This is genuinely interesting preliminary research, but I wouldn’t recommend self-medicating with yohimbine for anxiety disorders. The evidence is mixed, and given yohimbine’s stimulant effects, it could actually worsen anxiety in some people. If you’re dealing with phobias, cognitive behavioural therapy with a trained therapist remains the first-line treatment.

Side Effects of Yohimbine

Yohimbine is not a benign supplement. Its pharmacological activity as a stimulant means it comes with real risks, particularly at higher doses.

Common Side Effects

At typical supplemental doses (5-20 mg daily), commonly reported side effects include:

Increased heart rate (tachycardia)
Elevated blood pressure
Anxiety and nervousness
Tremors and shakiness
Dizziness
Headaches
Nausea and gastrointestinal discomfort
Flushing
Difficulty sleeping (when taken later in the day)
Frequent urination

Serious Side Effects

At higher doses or in susceptible individuals, more serious effects can occur:

Severe hypertension (dangerously high blood pressure)
Cardiac arrhythmias (irregular heartbeat)
Panic attacks
Hallucinations and psychotic episodes
Seizures
Priapism (prolonged, painful erection requiring medical attention) 9

A case series published in the Annals of Emergency Medicine documented multiple emergency department visits related to yohimbine supplements, including cases of hypertensive crisis and altered mental status 10.

The Dosing Problem

One significant issue with yohimbe bark supplements (as opposed to pharmaceutical yohimbine) is inconsistent dosing. A 2015 analysis of 49 yohimbe supplements found that the actual yohimbine content ranged from 0% to 154% of the amount listed on the label, with some products containing none at all and others containing potentially dangerous amounts 11. This makes it extremely difficult to dose safely.

Contraindications - Who Should Avoid Yohimbine

Given its stimulant effects on the cardiovascular system and central nervous system, certain groups should avoid yohimbine entirely:

1. People with Cardiovascular Conditions

Anyone with heart disease, arrhythmias, or uncontrolled hypertension should not take yohimbine. The increase in heart rate and blood pressure can be dangerous. If you have benign prostatic hyperplasia (enlarged prostate), yohimbine is also problematic as it can worsen urinary symptoms.

2. People with Mental Health Conditions

Yohimbine can trigger or worsen anxiety, panic attacks, and psychotic episodes. Those with anxiety disorders, post-traumatic stress disorder, bipolar disorder, or schizophrenia should avoid it. The noradrenaline release that yohimbine causes can destabilise mood and trigger manic or psychotic episodes in vulnerable individuals.

3. Pregnant and Breastfeeding Women

There is no safety data for yohimbine during pregnancy or breastfeeding. Given its effects on blood pressure and the cardiovascular system, it should be avoided entirely.

4. People Taking Certain Medications

Yohimbine has significant drug interactions:

Blood pressure medications: Yohimbine can oppose the effects of antihypertensive drugs, including beta-blockers, ACE inhibitors, and calcium channel blockers. Combining yohimbine with clonidine is particularly dangerous.

Antidepressants: MAO inhibitors combined with yohimbine can cause hypertensive crisis - a medical emergency. Tricyclic antidepressants may also interact. Even some SSRIs may have interactions.

Diabetes medications: Yohimbine may affect blood glucose levels and interfere with diabetes control.

Stimulants and caffeine: Combining yohimbine with other stimulants can compound cardiovascular risks.

If you take any prescription medications, consult your doctor before considering yohimbine.

Dosage Considerations

Prescription yohimbine hydrochloride is typically dosed at 5.4 mg three times daily (16.2 mg total) for erectile dysfunction. Studies on fat loss have used 20 mg daily in divided doses.

For over-the-counter yohimbe bark supplements, the unpredictable yohimbine content makes dosing recommendations essentially meaningless. What’s on the label may not reflect what’s in the bottle.

If you do choose to use yohimbine:

Start with the lowest possible dose to assess tolerance
Never exceed recommended doses
Avoid taking it with other stimulants
Take it earlier in the day to avoid sleep disruption
Monitor your blood pressure and heart rate
Stop immediately if you experience concerning symptoms

The Bottom Line

Yohimbine is one of those supplements where the theory sounds promising but the practical reality is more complicated.

For erectile dysfunction, it might help slightly but modern medications work far better. For fat loss, it only seems beneficial when combined with exercise and possibly fasting - and even then, the effects are modest. For phobias, it’s an interesting research avenue but not ready for clinical use.

What makes yohimbine genuinely concerning is its side effect profile. Unlike many supplements that are ineffective but harmless, yohimbine has real pharmacological activity that can cause real problems. The cardiovascular effects and potential for psychiatric symptoms make it unsuitable for many people, and the inconsistent dosing in supplements makes safe use difficult.

If you’re considering yohimbine, discuss it with your healthcare provider first, particularly if you have any cardiovascular conditions, mental health concerns, or take medications. There may be safer alternatives for whatever you’re trying to achieve.

References

Feldman HA et al. Impotence and its medical and psychosocial correlates: results of the Massachusetts Male Aging Study. J Urol. 1994.
Jang DJ et al. Efficacy of yohimbine on erectile function: systematic review and meta-analysis. Andrologia. 2022.
Ernst E, Pittler MH. Yohimbine for erectile dysfunction: a systematic review and meta-analysis of randomized clinical trials. J Urol. 1998.
Ostojic SM. Yohimbine: the effects on body composition and exercise performance in soccer players. Res Sports Med. 2006.
Sax L. Yohimbine does not affect fat distribution in men. Int J Obes. 1991.
Galitzky J et al. Alpha 2-antagonist compounds and lipid mobilization. Am J Clin Nutr. 1988.
Powers MB et al. Facilitation of fear extinction in phobic participants with yohimbine hydrochloride. Biol Psychiatry. 2009.
Meyerbroker K et al. Yohimbine combined with virtual reality exposure therapy. CNS Spectr. 2012.
Anderson C et al. Yohimbine and priapism. J Urol. 2013.
Pittler MH, Ernst E. Dietary supplements for body-weight reduction. Ann Emerg Med. 2016.
Cohen PA et al. Pharmaceutical quantities of yohimbine in dietary supplements. Drug Test Anal. 2016.