Yohimbine is an alkaloid that is found in the bark of a West African evergreen tree—the yohimbe tree. Yohimbine may help treat impotence that can be caused by a variety of factors, including medication side effects.

Commonly Used Product Names

  • Yohimbine hydrochloric acid (HCL) – a tablet available only by prescription
  • Yohimbe bark – available without a prescription in the following forms:
    • Capsule
    • Concentrated drops
    • Decoction
    • Tablet
    • Tea
    • Tincture

Yohimbe bark is often not standardized based on yohimbine content. It is, therefore, a less reliable source of yohimbine.

Sexual Effects

Yohimbine has a long history of being used as an aphrodisiac. More recently, some studies have suggested that it may have the following pro-sexual effects:

  • Helps to obtain and maintain erection
  • Enhances quality of erection
  • Helps retarded ejaculation

How Yohimbine Can Affect Sexual Function

The exact mechanism by which yohimbine helps sexual function is not clear. Two effects of yohimbine that likely contribute to its improvement of sexual function are:

Blocking of presynaptic alpha-2 adrenergic receptors – These are the receptors that the neurotransmitter norepinephrine uses as it moves through nerve cells to stimulate the sympathetic nervous system. When these receptors are blocked, the parasympathetic nervous system will dominate. One of the effects of the parasympathetic system is to increase blood flow to the penis. This aids the development and maintenance of an erection.

Increasing release of vasopressin – This substance, also called antidiuretic hormone (ADH), is believed to facilitate erectile function.

It usually takes two to three weeks of daily use before yohimbine begins to take effect.

A recent study found that low doses of yohimbine plus L-arginine glutamate was an effective treatment for low level erectile dystfunction, however, subsequent studies have not confimed this finding.

Side Effects

Since the effective level of yohimbine is close to its toxic level, it is not clear that its benefits outweigh its risks. Side effects of yohimbine include:

  • Anxiety
  • Nervousness
  • Panic attacks
  • Tremors
  • Elevated blood pressure and heart rate
  • Salivation
  • Nausea
  • Irritability
  • Insomnia
  • Urinary frequency
  • Excessive sweating
  • Fatigue

Cautions

Medications – Yohimbine may cause adverse reactions when taken with certain medications. These include:

  • MAO Inhibitors – When combined with yohimbine, MAO inhibitators can cause dangerously high blood pressure.

  • Note: MAOIs can cause adverse reactions when combined with many other types of drugs. These include other MAOIs, antidepressants, sympathomimetics, sedatives, narcotics, anesthetics, antihypertensive drugs, diuretics, antihistamines, buspirone, dexfenfluramine, and dextromethorphan. Ask your doctor and pharmacist for a complete directions about what to avoid.

  • Antidepressants – Yohimbine can interact with most types of antidepressants.
  • Antihypertensives – Yohimbine may increase blood pressure-lowering effects.
  • Nasal decongestants
  • Phenylpropanolamine-containing diet aids

Health Conditions – People with the following conditions probably should not take yohimbine:

  • High or low blood pressure
  • Chronic inflammation of the prostate gland
  • Heart, kidney, or liver disease
  • Panic or anxiety disorders
  • Sexual phobias or obsession-compulsion
  • History of gastric or duodenal ulcer disease
  • Schizophrenia
  • Bipolar disorder

Yohimbine is not usually prescribed for women; it should never be taken during pregnancy.

MAO inhibitors – Yohimbine is classified as an MAO inhibitor. Therefore, when taking MAOIs, you should not eat food with a high tyramine content. Examples include cheese, alcohol, pickled or marinated or smoked or cured or fermented foods, organ meats, nuts, peanut butter, fava beans, onions, avocados, and canned figs, chocolate, excess amounts of caffeine, or foods containing monosodium glutamate.