Yohimbe bark information

Source:
Used for centuries in Africa to enhance performance and virility, clinical studies indicate that Yohimbe is effective in some 80% of men with impotence. Yohimbe bark has traditionally been used in western Africa as a sexual aphrodisiac, especially in male erectile disorders. Found native to southwestern Nigeria, Cameroon, Gabon, and the Congo, the bark is stripped of the bark of an African tree (Corynanthe yohimbe or Pausinystalia yohimbe). These trees can reach height of ninety feet with a circumference of some forty feet.

Traditional uses:
Yohimbe has been used for centuries in African folk medicine to treat leprosy, coughs, treat fevers, as a local anesthetic, sexual aphrodisiac, etc. African tribal men would often chew on the bark prior to going to battle to increase their strength; however, its most popular use has been as an aphrodisiac and to improve erections.

Physiology:
While Viagra tends to be the medication of choice for erectile dysfunction, Yohimbe has proven to be an overall better remedy for improving both psychological well being of an individual and the erectile dysfunction. In order to understand the mechanism of action of Yohimbe, we must go over some physiology 101:

A large percentage of incurred physiological processes are not controlled voluntarily by an individual. These processes are controlled by the autonomic nervous system. The autonomic nervous system consists of two systems, the sympathetic and the parasympathetic nervous system. These two divisions of the nervous system counteract the action of the other to control our bodily functions.

More specifically, the sympathetic nervous system controls our “fight” and “flight” processes, while the parasympathetic system controls our “feed” and “breed” processes. The sympathetic division is responsible for the body's reaction to stress factors. When the sympathetic system is active, blood pressure, heart rate and respiration rate increase, blood vessels to the heart dilate, blood flow increases to the muscles, and pupils dilate. Think of a lion preparing to fight his hair is standing on end (giving the impression that he is larger), pupils are dilated, heart rate increases, and breathing becomes rapid. This reaction is accompanied by a constriction of arterial blood vessels and a decrease in the blood flow to the digestive organs and reproductive organs (an erection on a lion during a fight would be an unwanted obstacle, not to mention a vulnerable target for the opposition).

When stressful situations subside, parasympathetic nervous system will slow the heart rate and decrease blood pressure, moderate the breathing process, induce salivation, and increase blood flow to the digestive and reproductive organs. The signals from the sympathetic and the parasympathetic nervous system are transmitted via neurotransmitters that signal specific receptors. The neurotransmitter active on the sympathetic pathway is norepinephrine while parasympathetic pathway uses acetylcholine.

Yohimbe blocks the receptor sites for the neurotransmitter norepinephrine. Specifically, Yohimbe blocks the alpha-2-adrenergic receptors thus decreasing the action of the sympathetic nervous system so the parasympathetic system can prevail. By blocking the signals from the sympathetic system the parasympathetic system input prevails resulting in more blood flow to the female erectile organs. Secondary to the increased parasympathetic input there is also an increase in other parasympathetic activities including the digestive process.

In order to understand why the interference with alpha-2 adrenergic receptors work to facilitate erections, an individual must understand that during the normal flaccid genital state the norepinephrine is almost permanently docked to the alpha-2 adrenergic receptors. In order to achieve an erection there must be a decrease in the stimulation of alpha-2 adrenergic receptors. Yohimbe, by blocking the norepinephrine receptors (alpha-2-adrenergic receptors), increases the in freely circulating norepinephrine. The additional norepinephrine (adrenaline) subsequently acts as a hormone to exert the typical adrenergic effect on the heart, resulting in an increased heart rate, possible palpitations, etc. The increase norepinephrine also causes a reaction similar to amphetamines; men experience an increase sense of alertness sexual arousal.

This makes Yohimbine very unique in that the herb has a dual aphrodisiac function: First the herb improves sexual function by displacing hormonal epinephrine from alpha-2 adrenergic receptors in the pelvic area by increasing blood flow to the female erectile organs. Second the herb, increases the levels of free norepinephrine which subsequently results in an increase sense of alertness and sexual arousal.

Clinical Studies:
There have been numerous clinical studies that confirm Yohimbe’s effectiveness. For example, in the February 1998 issue of the Journal of Urology, researchers from the University of Exeter Medical School in England surveyed clinical trials involving the herb and concluded that Yohimbine should be used in the first line of treatment for erectile dysfunction. The benefits of Yohimbe far outweigh the risks associated with the herb.

Additional clinical studies have shown that Yohimbe to be effective in up to 80% of men with erectile dysfunction. These results rival the clinical results of Viagra that show a positive effect in some 75%-83% of the population tested. Yohimbe was shown to be most effective in men who suffer from impotence secondary to psychological, vascular or diabetic in origin.

The herbal supplement did not produce significant improvement in males with impotence caused by organic nerve damage (which is only attributed to a small percent of those individuals with impotence). Yohimbe was also shown to increase sexual stamina and prolong erections in men who are free from the complications of impotence.

In addition, the promising value of Yohimbe is not only the herbs role as a treatment for erectile dysfunction but its power to enhance sexuality in healthy subjects. Yohhimbe is also prescribed as an effective weight loss supplement. Lise Alschuler M.D., medical director at Bastyr University in Washington stated that “Yohimbe is my number one choice for weight loss. I start with a very small dose and the gradually increase the intake while monitoring the patient’s tolerance levels.”

Modern day uses:
Today, Yohimbe is not only prescribed by physicians and herbal specialist for erectile dysfunction but for the following positive benefits:

Effective in restoring potency in diabetic and heart patients who suffer from impotency
Has been used in traditional medicine to treat angina and hypertension
Effective weight loss agent
Increase overall stamina and endurance
Promotes generalized feeling of well being

Precautions and/or side effects:
Individuals with preexisting medical conditions should consult with their physician particularly if they are taking prescription or over-the-counter-medications or supplements. Women who are pregnant or breast feeding and children should also consult with there physician prior to taking any new supplements. Yohimbe should not be taken with food or drinks that contain a high amount of tyramine, i.e. avoid aged cheese; aged or cured meats (e.g., air-dried sausage); any potentially spoiled meat, poultry, or fish; broad (fava) bean pods; Marmite concentrated yeast extract; sauerkraut; soy sauce and soy bean condiments; and tap beer. Tyramine is a sympathomimetic agent that can potentate the side effects of the supplement.

Yohimbe should be taken with caution, the herb should not be consumed by individuals who are currently taking antidepressants, sedatives, certain antihistamines, stimulants and/or hypertensive medications. Yohimbe is considered to be a short term MAO inhibitor; therefore, individuals with a history of hypertension should use caution prior to taking the herb. Yohimbe may induce excessive adrenal or sympathetic nerve stimulation, anxiety, panic attacks, irritability, sweating, flushing, hypertension, headaches, dizziness, nausea, skin flushing, frequent urination, water retention, increased body temperature, upset stomach, etc. Yohimbe is also reported to have mild hallucinogenic properties in some individuals. These effects include audio and visual hallucinations, and feelings of euphoria. Most of the side effects mentioned above occur when individuals take the supplement in higher than recommended dose.

Most physicians recommend taking Yohimbine on a daily basis to avoid the side effects of nervousness and possible agitation. Practically all hormones have the effect of inhibiting their own production, usually via what is called a negative feedback system. (Messages are carried through blood plasma to the hypothalamus-pituitary systems when there is an increase in neurotransmitters to limit their production in the future.) The adrenal hormones or neurotransmitters epinephrine and norepinephrine are no exception (return to homepage).