Yohimbine hydrochloride is a standardized form of yohimbine, a chemical found specifically in the herb yohimbe. It is being studied as a possible treatment for erectile dysfunction and low libido, or low sex drive, due to its widespread use as an aphrodisiac in Africa, though it has not yet been clinically proven to treat either of these conditions. It is also used to improve the efficacy of some antidepressants and to counteract the sexual side effects of antidepressant medications.
As a supplement, yohimbine hydrochloride is extracted from the bark of Pausinystalia yohimbe, a species of plant with psychoactive properties. This separates the yohimbine alkaloid from the rest of the plant. The alkaloid is then purified and inserted into a dissolvable form or a capsule pill for administration as a drug.
The amount of yohimbine in yohimbe bark is actually quite low, making consumption of the plant itself very ineffective for the treatment of sexual disorders. When the yohimbine alkaloid is extracted from many plants and inserted into a pill, however, the effectiveness of this alkaloid can be potent. Studies show that even moderate use of yohimbine hydrochloride can cause changes in blood pressure, anxiety levels and a person's heart rate.
Only a few studies show it is effective as a medical treatment. In some cases, it helped increase ejaculate volume in dogs, with effects lasting up to five hours. In a controlled study involving human participants, regular administration of this drug was shown to treat orgasmic dysfunction in men, a condition that makes it impossible to reach orgasm. There is no clinical evidence it can increase the libido or treat erectile dysfunction, two conditions for which this drug is mainly used.
Yohimbine hydrochloride has been shown to improve the efficacy of some drugs, including alpha-2 receptor antagonists, which are types of antidepressant drugs. According to one study, the drug enhanced the antidepressant effects of drugs classified as alpha-2 receptor antagonists, which may help it work better in people with certain types of depression. This study was conducted on mice, however, not humans, so its effectiveness for humans is not known.
This drug can cause several side effects, including high blood pressure, increased heart rate, anxiety, and dizziness. Nausea, vomiting, shaking or tremors, and insomnia also are possible. It also can worsen anxiety, making it unsafe for people with anxiety disorders, such as social anxiety disorder.
Yohimbine hydrochloride is not safe for people with a history of psychiatric disorders or kidney problems. Women who are breastfeeding, are pregnant, or think they may be pregnant should not take this drug. People currently on MAO inhibitors, a type of antidepressant, also cannot safely take this drug, and people who take tricylic antidepressants, phenothiazines or drugs used to control high blood pressure should avoid this drug as well, unless medically advised to take it.