Other common name(s): yohimbe, yohimbe bark, yohimbine hydrochloride, johimbe, Actibine®, Aphrodyne®, Dayto Himbin®, Yocon®, Yohimex®, Yomax®
Scientific/medical name(s): Pausinystalia yohimbe (Corynanthe yohimbe)
Yohimbe is an evergreen tree native to western Africa, specifically the countries of Nigeria, Cameroon, Gabon, and the Congo. It can reach a height of 90 feet. The dried bark is used in folk and herbal remedies.
The drug yohimbine hydrochloride (called yohimbine), is derived from yohimbe bark, and has been approved by the United States Food and Drug Administration for prescription use only.
Yohimbe bark has been used as an aphrodisiac (sexual stimulant) for many years. Yohimbe bark has been declared an unsafe herb in Germany because of such complications as increased heart rate and blood pressure, and even kidney failure. In the United States, supplements that are labeled as containing yohimbe bark often contain very little of it.
On the other hand, yohimbine hydrochloride, which is the substance in yohimbe bark thought to help with erections, is more carefully controlled so that it does contain the labeled ingredient. It is mainly used as a treatment for erectile dysfunction (male impotence), although there are concerns about its side effects and interactions with other medicines, alcohol, and even some foods. Yohimbine hydrochloride is often called simply yohimbine, although it is made under several brand names.
How is it promoted for use?
Yohimbe bark extracts are promoted as aphrodisiacs and sexual enhancers for men and women. Proponents say that yohimbe extracts are powerful antioxidants that can prevent heart attacks. Some also tout it is as a stimulant, anti-depressant, and an aid to weight loss.
Yohimbine hydrochloride is thought to be the most important component of yohimbe bark. The drug yohimbine is available by prescription for the treatment of impotence. It is supposed to improve blood flow to the penis. It has also been promoted to treat exhaustion, drug overdose (from clonidine), and a form of low blood pressure that occurs when standing (postural hypotension). It can also be used to enlarge the pupil of the eye.
What does it involve?
Yohimbe bark and bark extracts are sold in capsules, tablets, liquids, and powders. Capsules and tablets are most often swallowed. Some people make the bark into a tea, while others place the powdered bark under the tongue or sniff it.
The yohimbe bark extracts and supplements labeled yohimbine that are sold in health food stores and through the Internet contain varying amounts of yohimbe as well as other ingredients. Researchers from the FDA analyzed a number of commercial yohimbe bark products available over the counter. They found that the supplements contained only 7% or less of the amount of yohimbine that would be found in actual yohimbe bark, which suggests that they contained little or no yohimbe.
On the other hand, the prescription form of yohimbine is strictly regulated by the FDA. It is approved only for the treatment of impotence, and is available in tablets and capsules. The standard dosage is 5.4 mg taken 3 times a day for not more than 10 weeks.
What is the history behind it?
In Africa, yohimbe has been used for generations as an aphrodisiac and a treatment for impotence. It was also used to treat fevers, leprosy, high blood pressure, and heart problems. In addition, it was used by warriors as a stimulant before battle. The powder was sometimes smoked to induce hallucinations, and yohimbe poultices were placed on the skin as an antiseptic and treatment for pain. In the 1890s, medicinal use of yohimbe appeared in Europe. It has been used to treat impotence for over 100 years.
After manufacturers purified the substance called yohimbine from the tree’s bark, it has been sold by prescription only in the United States. It was in use by 1938, before new drugs were required to submit New Drug Applications and to be reviewed by the FDA, so sales of the drug were allowed to continue. Its popularity has decreased as Viagra and similar drugs were approved starting in the late 1990s. Even so, there is concern that the yohimbe trees of Africa are being killed by over-harvesting because of its popularity as a drug and dietary supplement.
What is the evidence?
Most clinical trials have looked at yohimbine, rather than at yohimbe bark. Clinical trials have found contradictions regarding the effectiveness of yohimbine for treating impotence. The American Urological Association guidelines on treatment of impotence state that they could not draw conclusions about the how well yohimbine works in the treatment of ED, and that larger studies are needed to evaluate it.
A randomized clinical trial found that yohimbine may be a useful treatment for impotence not caused by a physical problem. Another randomized clinical study found that yohimbine was no better than a placebo as a first treatment for impotence that had some physical basis. Other studies with yohimbine have shown it helps some with mild erectile problems, even those that have a physical basis. No studies to date have compared yohimbine to newer treatments for impotence.
Another clinical review concluded that yohimbine has a modest effect on impotence caused by psychological factors, but not on impotence due to physical causes. It appears that more research needs to be done to clarify the role of yohimbine in the treatment of impotence.
It is important to note that these studies were done using the drug yohimbine. Extracted chemicals are not the same as yohimbe bark. Studies of yohimbine would be expected to give different results from studies that used the raw plant. The unpurified plant extract would have different amounts of active compounds, more compounds that may cause unexpected effects, and many other differences.
Yohimbine is now being used in combination with other substances and may be helpful for men who cannot take the newer drugs for impotence. A 2002 study looked at yohimbine combined with L-arginine glutamate (a substance that is thought to affect erections), given to 45 men as a one-time dose 1-2 hours before intended sexual intercourse. Results showed that it worked better than placebo, although men with mild to moderate erectile dysfunction had more improvement than those with more severe problems.
Yohimbine has also been tested in small studies with people who have low blood pressure and in those who faint after standing up. It appeared to be somewhat helpful, but more studies need to be done before it can be recommended for this use. Early studies have also suggested that it can enlarge (dilate) the pupil of the eye, but more information is needed.
Are there any possible problems or complications?
This product is sold as a dietary supplement in the United States. Unlike drugs (which must be tested before being allowed to be sold), the companies that make supplements are not required to prove to the Food and Drug Administration that their supplements are safe or effective, as long as they don't claim the supplements can prevent, treat, or cure any specific disease.
Some such products may not contain the amount of the herb or substance that is written on the label, and some may include other substances (contaminants). Actual amounts per dose may vary between brands or even between different batches of the same brand.
Most such supplements have not been tested to find out if they interact with medicines, foods, or other herbs and supplements. Even though some reports of interactions and harmful effects may be published, full studies of interactions and effects are not often available. Because of these limitations, any information on ill effects and interactions below should be considered incomplete.
Yohimbine and yohimbe bark may increase heart rate and raise blood pressure. People who should not take yohimbe or yohimbine include those with high blood pressure; heart, kidney or liver disease; and anxiety or nervous disorders. Those who drink alcohol and those who take antidepressants, anti-psychotic drugs, methadone, certain nausea medicines, or opioid pain medicines (such as morphine) should not use yohimbe or yohimbine. Other potential interactions between yohimbe and other drugs and herbs should be considered. Some of these combinations may be dangerous. Always tell your doctor and pharmacist about any herbs you are taking.
Side effects of yohimbe bark or yohimbine include difficulty breathing, chest pain, palpitations, anxiety, queasiness, sleeplessness, and vomiting. Normal doses of yohimbine can cause the blood pressure to go up. Large doses of yohimbine (40 mg per day or more) can cause the blood pressure to go down, and have been blamed for a few heart attacks and even deaths. Yohimbine can make heart disease or blood pressure problems worse. The less common side effects that do not usually require medical attention include dizziness, headache, flushing, nausea, nervousness, sweating, and tremors.
People with emotional or psychiatric problems may have worsening of post-traumatic stress disorder, sleeplessness, and anxiety. New onset of panic attacks or manic episodes have been reported. Yohimbine has been linked to psychotic episodes (losing touch with reality).
Yohimbine can also act as a monoamine oxidase inhibitor (MAOI). Foods that contain tyramine, such as beer, red wine, liver, aged or smoked meats, and aged cheese can raise blood pressure to dangerous levels if you eat them while taking yohimbine.
Yohimbine or yohimbe bark should not be used by children, elderly people, or women who are pregnant or breast-feeding.
Yohimbe bark is on the Commission E (Germany's regulatory agency for herbs) list of unapproved herbs. This means that it is not recommended for use because it has not been proven to be safe or effective.
More information from your American Cancer Society
The following information on complementary and alternative therapies may also be helpful to you. These materials may be found on our Web site (www.cancer.org) or ordered from our toll-free number (1-800-ACS-2345).
The ACS Operational Statement on Complementary and Alternative Methods of Cancer Management
American Urological Association. Management of Erectile Dysfunction ('05/Updated '06). Available at: http://www.auanet.org/guidelines/edmgmt.cfm. Accessed May 10, 2007.
Betz JM, White KD, der Marderosian AH. Gas chromatographic determination of yohimbine in commercial yohimbe products. J AOAC Int. 1995;78:1189-1194.
Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Austin, Tx: American Botanical Council; 1998.
Brinker NDF. Herb Contraindications and Drug Interactions, Second Edition. Sandy, Ore: Eclectic Medical Publications; 1998.
Cassileth B. The Alternative Medicine Handbook. New York, NY: W. W. Norton & Co; 1998.
Center for Drug Evaluation and Research. Personal communication, November 1, 2005.
Drug Digest. Yohimbe. Available online at www.drugdigest.org/DD/DVH/HerbsWho/0,3923,4048|Yohimbe,00.html. Accessed May 10, 2007.
Ernst E, Pittler MH. Yohimbine for erectile dysfunction: A systemic review and meta analysis of randomized clinical trials. J Urol. 1998;159:433-436.
Fetrow CW, Avila JR. Professional's Handbook of Complementary and Alternative Medicines. Springhouse, Pa: Springhouse Corp; 1999.
Gruenwald J, Brendler T, Jaenicke C, eds. PDR for Herbal Medicines, Third Edition. Thomson PDR, Montvale NJ, 2004.
Kunelius P, Hakkinen J, Lukkarinen O. Is high-dose yohimbine hydrochloride effective in the treatment of mixed-type impotence? A prospective, randomized, controlled double-blind crossover study. Urology. 1997;49:441-444.
Lebret T, Herve 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 Jun;41(6):608-13.
Mayo Clinic Drugs and Supplements. Yohimbine (Oral Route). Available at: www.mayoclinic.com/health/drug-information/DR601453. Accessed May 10, 2007.
Memorial Sloan Kettering. Yohimbe. Available at www.mskcc.org/mskcc/html/69423.cfm. Accessed May 10, 2007.
Morales A. Yohimbine in erectile dysfunction: the facts. Int J Impot Res. 2000 Mar; 12 Suppl 1:S70-74.
National Institutes of Health. Summary of data for chemical selection: Yohimbe bark extract / yohimbine. Available at National Toxicology Program’s Web site: http://ntp.niehs.nih.gov/ntp/htdocs/Chem_Background/ExSumPdf/Yohimbe.pdf. Accessed 5/10/07.
PDR Health. Yohimbe. Available at: www.pdrhealth.com/drug_info/nmdrugprofiles/herbaldrugs/103010.shtml. Accessed May 10, 2007.
Pittler MH, Ernst E. Trials have shown yohimbine is effective for erectile dysfunction. BMJ. 1998;317:478.
Stine SM, Southwick SM, Petrakis IL, et al. Yohimbine-induced withdrawal and anxiety symptoms in opioid-dependent patients. Biol Psychiatry. 2002 Apr 15;51(8):642-51.
Teloken C, Rhoden EL, Sogari P, et al. Therapeutic effects of high dose yohimbine hydrochloride on organic erectile dysfunction. J Urol. 1998;159:122-124.
Vogt HJ, Brandl P, Kockott G, et al. Double-blind, placebo-controlled safety and efficacy trial with yohimbine hydrochloride in the treatment of nonorganic erectile dysfunction. Int J Impot Res. 1997;9:155-161.
Wagner G, Saenz de Tejada I. Update on male erectile dysfunction. BMJ. 1998;316:678-682.
Note: This information may not cover all possible claims, uses, actions, precautions, side effects or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for consultation with your doctor, who is familiar with your medical situation.
Last Revised: 11/28/2008