by Karen Schroeder, MS, RD
Yohimbine is an alkaloid that is found in the bark of a West African evergreen treethe yohimbe tree. Yohimbine may help treat impotence that can be caused by a variety of factors, including medication side effects.
- 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.
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
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: AnxietyNervousnessPanic attacksTremorsElevated blood pressure and heart rateSalivationNauseaIrritabilityInsomniaUrinary frequencyExcessive sweatingFatigue 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 decongestantsPhenylpropanolamine-containing diet aids Health Conditions People with the following conditions probably should not take yohimbine: High or low blood pressureChronic inflammation of the prostate glandHeart, kidney, or liver diseasePanic or anxiety disordersSexual phobias or obsession-compulsionHistory of gastric or duodenal ulcer diseaseSchizophreniaBipolar 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. RESOURCES: American Cancer Society http://www.cancer.org National Center for Complementary and Alternative Medicine
http://nccam.nih.gov References Sexual Pharmacology: Drugs that Affect Sexual Function . W.W. Norton & Company; 1996. The American Pharmaceutical Association Practical Guide to Natural Medicines . William Morrow and Company, Inc.; 1999. Lebret T, Herv JM, Gorny P, et. al. Efficacy and safety of a novel combination of L-arginine glutamate and yohimbine hydrochloride: a new oral therapy for erectile dysfunction. Eur Urol. 2002;41(6):608-613. Guay AT; Spark RF; Jacobson J; Murray FT; Geisser MEYohimbine treatment of organic erectile dysfunction in a dose-escalation trial.Int J Impot Res. 2002; 14(1):25-31 Last reviewed December 2006 by Jill D. Landis, MD Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
