Resume. This article generalizes literature data of yohimbine efficiency in treatment of patients with erectile dysfunction (ED) and presents results of own experimental and clinical studies of new preparation YOHIMBEX-HARMONY composed of yohimbine hydrochloride, ginseng root, selenium, zinc and ascorbic acid. In experiments with make rats more expressed stimulating effect of YOHIMBEX-HARMONY as compared to yohimbine on sexual motivation had been ascertained. As distinct from yohimbine, this new combined preparation facilitates better copulation efficiency. The results of clinical testing prove that YOHIMBINE-HARMONY is effective in treatment of patients with sexual dysfunction conditioned by ED. In 93.3% patients with different forms of copulation dysfunction the use of this preparation resulted in the recovery of a full-value erection or capability of sexual act execution. The search of new drugs for treatment of sexual dysfunction in males is a topical medical and social problem. Failure of erectile component of copulative function is one of most spread sexual dysfunction forms. The erectile dysfunction in males is defined as an incapability to achieve and/or to maintain erection, sufficient for sexual act execution. Episodic trouble of the erectile component of copulative function is noted in 10% males over 21 year, some reduction of erectile function – in 52% males aged from 40 to 70 years and chronic ED – in 25% males over 65 years. Age erectile function failures most often develop on the background of cardiovascular diseases, diabetes mellitus and may result from the use of drugs or from psychogenic factors. Yohimbine (methyl ether of (16a, 17a)-17-hydroxiyohombane-16a-carbonic acid), contained in plants of Rubасеае family, is one of preparations, which widely used in sexological practice. N.S.T. Gardner was the first who mentioned in 1909 the use of this preparation as an aphrodisiac Popularity of yohimbine is proved by the fact in 1997 only in USA more than 20 pharmaceutical companies manufactured yohimbine-based reparations. After demonstration that yohimbine is a selective blockator of alpha-2-adrenoreceptors interest of surveyors to this substance has sharply grown. In addition to wide use in fundamental studies, characterizing different effects of a-adrenoreceptors, experiments were conducted for studying yohimbine effect on sexual behavior of experimental creatures (male rats). By data of J.T. Clark et al. (1984) yohimbine stimulates sexual desire (analog of human libido) and copulative behavior. Yohimbine (as well as some other adrenoreceptors) stimulates the mating process and sexual activity of elder creatures (Smith E.R., Davidson J.M., 1990). Yohimbine injection positively impacts sexual motivation in rats with inhibited sexual behavior, caused by lithium chloride (Peters R.H. et al, 1988). The results of studies by J.T. Clark et al. (1984) had shown that testosterone did not participate in the realization of yohimbine effect on sexual desire. Yohimbine injection in the ventricle of the brain results in changes of sexual behavior similar to those registered with intra-abdominal injection (Sala M. et al., 1988). Numerous works were devoted to yohimbine use for treatment of patients with ED. A number of surveyors stated some doubts concerning yohimbine efficiency. It is an opinion of R.C. Rosen and А.К. Ashton (1993) "...treatment with yohimbine can positively impact sexual function, however the results are far unconvincing”. The same conclusion was also drawn by М.Р. Сагеу et al. (1994): "... the existing data make us think that yohimbine cannot be effective”. For example, during randomized clinical cross examination inefficiency of yohimbine use in combination with isoxuprine (agonist of noradrenoreceptors) was ascertained in comparison with pentoxyphylline for treatment of patients with combined vasculogenic impotency (lesion of arterial bead plus pathologically intensive vein outflow from corpus cavernosum penis) (Knoll L.D. et al., 1996). Nevertheless, a number of works within latest years attest the counter. So, К. Mann et al. (1996) had studied therapeutic efficiency of yohimbine in patients with ED during double random placebo-controlled examination. After detailed clinical, urologic and psychiatric examination of 31 patients they were divided into two groups: with organic troubles (vasculogenic, neurogenic, sharp changes by data of clinical analyses) and without them. Yohimbine daily dose 15 mg was applied within 7 weeks. Changes detectable against Clinical Global Impression (CGI) scale were assumed as a basic criterion of effective treatment. In addition to this nocturnal penis swelling (NPS) was recorded. At the end of experiment trends to improvement of indicators against GGI scale in the group of patients using placebo and yohimbine. However, only in patients without organic troubles improvement of indicators after yohimbine application was statistically confident. In doing so, there was no correlation with NPS parameters, which yohimbine did not affect. D.L. Rowland et al. (1997) had studied the efficiency of yohimbine application in patients with psychogenic ED (existence of cardiovascular and neurological pathologies was excluded) and in volunteers without it. Parameters of nocturnal penis tumescence and response to visual sexual stimulation within 4 weeks of testing and results of evaluation of sexual activity of patients against a 7-point scale were recorded in a logbook. It was demonstrated that the preparation did not affect sexual activity in healthy males (only insignificant ejaculation delay with visual stimulation was noted). With application of yohimbine in patients were ED erection response on visual sexual stimulation and with masturbation s (but not in sexual intercourse) sharply rose, i.e. beneficial effect of the preparation was noted with the presence of a female partner. As compared with volunteers in the group of patients with ED lower indicators of NPS were recorded, which fact shows possible role of somatic diseases in ED etiology. Te use of yohimbine by no means affected NPS parameters. Only 30% patients, who used yohimbine, evaluated the result of treatment as very good while the rest – as so-so. The authors have concluded that yohimbine for these patients must be used not instead of therapy, aimed in elimination of sexual dysfunction, but as an addition to it (considering libido stimulation). М.Р. Сагеу and В.Т. Johnson (1996) have analyzed results of clinical testing of yohimbine and yohimbine-containing preparations, which were published in 35 works within the period from 1966 to 1993. This meta-analysis has summarized data of controllable and uncontrollable clinical tests of yohimbine, which was used both individually and in combination with other preparations. The obtained results prove the fact that use either of yohimbine or of yohimbine-containing preparations improves erectile erection. Some works stated that NPS parameters with the use of yohimbine had not changed. Hence, in usual doses this preparation does not affect erection physiology. By acting on CNS yohimbine modulates psychical stresses, responsible for sexual activity, due to which erection response may reach its physiological maximum. Taking into consideration, that yohimbine is effective only in patients with troubles of copulative cycle erectile component, we have developed a unique preparation YOHIMBEX-HARMONY, which is now manufactured by CJSC “Borschagovsky CPP”. In addition to yohimbine composition of this preparation includes ginseng root, which is widely used for treatment of troubles of copulative function neurohumoral component, microelements (zinc and selenium) and ascorbic acid, which play a very important role in provision of normal functioning of sexual (reproduction) system organs. The results of experimental study of preparation YOHIMBEX-HARMONY demonstrate that this preparation stimulates sexual behavior of male rats. YOHIMBEX-HARMONY as well as yohimbine itself stimulates first of all mating initiation and re-initiation after ejaculation, thus intensifying copulation rate and raising mating process efficiency. In clinical practice preparation YOHIMBEX-HARMONY was used in 30 patients aged from 20 to 52 years; 18 patients were treated against pathogenic, 6 – combined and 6 – interoreceptive-psychogenic copulative dysfunction. The preparation was used in dose 1 capsule 3 times a day within 20 days. On the basis of data of subjective evaluation by patients an expressed trend to erection improvement was noted. So, before treatment all patients had no full-value erection and only 10 patients (33.3%) noted partial erection. Upon treatment course with preparation YOHIMBEX-HARMONY full-value erection recovered in 16 patients (53.3%) and 28 patients (93.3%) appeared able to execute sexual act. On the basis of subjective feelings (erection length, libido expressiveness, capability to execute a full-value sexual act) 86.7% patients evaluated treatment efficiency as either sufficient or high. In 93.3% cases preparation was well or very well tolerable. CONCLUSIONS Results of clinical application of yohimbine have shown, that it is a promising drug for treatment of patients with ED. New homemade combination preparation YOHIMBEX-HARMONY, containing in addition to yohimbine ginseng root powder, selenium, zinc and ascorbic acid, when compared with mono-preparation yohimbine, give a more expressed action on copulation efficiency in experiments on male rats. Clinical tests of YOHIMBEX-HARMONY have proved that this preparation is an effective drug for treatment of sexual troubles, in particular, of copulative dysfunction in males.