Aphrodin, corymbin, corynin, hydroergotocin,
johimbin, quebrachin, quebrachina, yohimbenin,
N yohimbin, yohimbina, yohimbinum, yohimvetol Substance type: aspidosperma alkaloid, indole
Yohimbine was first extracted from the bark of Pausinystalia yohimba and described in the
nineteenth century. It is a typical alkaloid in plants
from the Apocynaceae Family and is related to the
Rauvolfia alkaloids, and it constitutes the primary
alkaloid (1 0/0) in Alstonia angustifolia. It is also
present in some species of Rauvolfia, especially the
African species Rauvolfia macrophylla Stapf
(Timmins and Court 1974).
Yohimbine was once regarded as an MAOMonoamine Oxidase, an enzyme that catalyses the metabolism of many drugs (e.g., DMT, dopamine and serotonin).
inhibitor, a view that is no longer considered accurate.
Rather, it is simply an a -adrenergic blocker
that consequently stimulates the release of noradrenaline
at the nerve endings. This makes
noradrenaline available in the corpus cavernosum
and results in an erection (Roth et al. 1994, 955*;
As a sympathicolytic agent, [yohimbine]
dilates the peripheral blood vessels and
reduces blood pressure. The aphrodisiac effect
is explained through a vasodilatation of the
genital organs and an increased excitability of
the reflexes in the sacral medulla. (Roth et al.
Yohimbine's aphrodisiac and virility-enhancing
effects, and its therapeutic efficaciousness in
treating impotence, have been demonstrated in a
number of clinical double-blind studies (Buffum
1982; Miller 1968; Sobotka 1969).505
Consequently, yohimbine hydrochloride has
been approved as a specific medicine for the treatment of impotence (sexual neurasthenia). The
recommended dosage is 5 to 10 mg taken three
times daily as a short-term treatment over three to
four weeks. Higher individual dosages (15 to 25
mg) result in psychoactive effects that are somewhat
reminiscent of those of LSD, but with much
less emotional content and an emphasis on
physical phenomena (sexual desire, erotic enjoyment,
and increased sensations of pleasure).
Overdoses can be unpleasant but do not appear to be particularly dangerous (cf. Lewin 1992, 750*):
A chemist had taken an almost 1000-fold
dosage (1.8 g). He became unconscious for a
few hours (during which time a pronounced
priapism was observed) but was able to be
discharged from the hospital within a day.
(Roth et al. 1994,956*)
Commercial Forms and Regulations
The alkaloid is available as yohimbine hydrochloride.Yohimbine is a prescription medication.
(from Geschwinde 1996, ·145 f. *; Hofmann
1954;Lewin 1992*; Rompp 1995,5093*; Roth
et al. 1994*; supplemented)
See also the entries for Alstonia scholaris, Corynanthe
spp., and Pausinystalia yohimba.
Buffum, John. 1982. Pharmacosexology: The effects
of drugs on sexual function-a review. Journal of
Psychoactive Drugs 14 (1-2): 5-44.
Finch, N., and W. I. Taylor. 1962. Oxidative
transformation of indole alkaloids. 1:
Preparation of oxindoles from yohimbine.
Journal of the American Chemical Society
Hofmann, Albert. 1954. Die Isolierung weiterer
Alkaloide aus Rauwolfia serpentina Benth.
Helvetica Chimica Acta 37:849-65.
Lambert, G. A., W. J. Lang, E. Friedman, E. Meller,
and S. Gershon. 1978. Pharmacological and
biological properties of isomeric yohimbine
alkaloids. European Journal ofPharmacology
Leary, Timothy. 1985. Auf der Suche nach dem
wahren Aphrodisiakum und e1ektronischer Sex.
Sphinx Magazin 35.
Miller, W. W. 1968. Afrodex in the treatment of male
impotence: A double-blind cross-over study.
Current Therapeutic Research 10:354-59.
Poisson, J. 1964. Recherches recentes sur les
alcaloYdes du pseudocinchona et du yohimbine.
Ann. Chim. 9:99-121.
Porst, H. 1996. Orale und intracavernose
Pharmakotherapie. TW Urologie Nephrologie 8
Sobotka, J. J. 1969. An evaluation of Afrodex in the
management of male impotency: A double-blind
cross-over study. Current Therapeutic Research
Timmins, Peter, and William E. Court. 1974.
Alkaloids of Rauwolfia macrophylla.
Weyers, Wolfgang. 1982. Die Empfehlung in derSelbstmedikation. Heusenstamm: Keppler Verlag.