Yohimbe: what it is
Yohimbe is the name of the drug derived from the tree Pausinystalia yohimbe (Fam. Rubiaceae ), particularly widespread in the regions of western Africa. The active ingredient that characterizes it is known as yohimbine, sometimes Italianized in the term "ioimbina".
Active principles
Yohimbe is the drug obtained from the inner part of the bark of the Pausinystalia yohimbe tree; inside we find about 5% of pharmacologically active substances, among which the best known is the indole alkaloid Yohimbine, naturally accompanied by substances of similar structure and activity (ioimbinina, ioimbenina).
Properties and Uses
Yohimbe and Yohimbine are traditionally considered to be aphrodisiacs and stimulants. In the first case we refer to their ability to stimulate sexual desire and performance; in the second to the enhancement of physical or intellectual abilities, to produce psychedelic effects at high doses. In the western world, Yohimbine is known above all as a useful substance to promote sports performance, improve erection and promote weight loss.
Action mechanism
All these effects are due to the ability of Yohimbine to interact with α2-adrenergic receptors, important in regulating the release of neuerotransmitters from nerve endings. In fact, these autocettors act as a kind of thermostat, able to sequester a part of the liberated norepinephrine and inhibit its release in relation to the quantity captured. Yohimbine, in particular, acts as a powerful and selective alpha-2-adrenergic antagonist (blocker); thanks to this activity, the "inhibitory feedback" control exercised by the α2-adrenergic receptors fails, with an inevitable increase in noradrenergic activity. The main results of this effect are a greater dilation of the blood vessels of the genitals and an increase in lipolysis (due to the reduction of the antilipolytic effect due to the stimulation of alpha-adrenergic receptors). Despite these assumptions, the mechanisms by which yohimbine carries out its effects have not yet been fully clarified.
Effectiveness
With regard to the alleged usefulness of Yohimbine as an aphrodisiac substance, numerous studies have been conducted. In light of the results gathered, the current orientation is in attributing a certain benefit to this active principle in the treatment of erectile dysfunction, although its effects are considered modest and not always effective. The aphrodisiac action of ioimbina can be enhanced by the simultaneous intake of arginine, an amino acid necessary for the synthesis of nitric oxide (a very important substance in the mechanism of erection).
Mode of use
Since the Yohimbe drug may contain different percentages of Yohimbine and similar substances, the effects of its characterizing active ingredient have been studied by isolating it from the phytocomplex and administering it at doses normally between 15 and 30 mg - often divided into two or three assumptions daily - in the form of yohimbine hydrochloride (a medicine that can only be purchased by prescription). Fasting is recommended, especially when it is intended to promote the slimming process.
Side effects
Especially when used at high dosages, Yohimbine can produce a long list of side effects, such as tachycardia, hypertension, insomnia, headache, anxiety, hallucinations and panic attacks; its use is not recommended to patients with heart, liver and kidney diseases, or mental disorders, as well as the association with other stimulating preparations, such as caffeine, ephedrine or amphetamines.
Generally speaking, a prudent approach may be to start by taking Yohimbine at dosages around 3 times lower than the optimal dose, to then gradually increase in the following days. In this way any side effects will appear in a less serious and more controllable way.
Due to the numerous contraindications and possible drug interactions, a medical consultation is necessary before taking Yohimbine preparations. Currently (May 2017), Yohimbe is not marketable in Italy as a food supplement.
