Corynanthine (Yohimban Alkaloid · Alpha-2 Partial Agonist · Yohimbe Co-alkaloid)

Compound	Corynanthine
Chemical class	Alkaloid — Indole (Yohimban; Yohimbine Diastereomer)
CAS	483-10-3
Primary source	Pausinystalia johimbe (yohimbe bark), Rauwolfia spp.
Key applications	Alpha-2 adrenoceptor partial agonist (opposite to yohimbine), antihypertensive
Claim strength	Moderate
Typical form	Yohimbe bark extract co-constituent; isolated corynanthine
Buy from Herbuno	Yohimbe Extract Powder - Pausinystalia johimbe → Yohimbe Bark Liquid Extract (Water Soluble) - Pausinystalia johimbe →

Commercial source: Corynanthine is commercially available as a co-constituent of Pausinystalia johimbe bark extract alongside yohimbine. Isolated corynanthine is available from specialist chemical suppliers as a research-grade material. See sourcing options below. Traditional use: Shares yohimbe bark’s traditional use as an aphrodisiac and stimulant in West African medicine. Corynanthine was not individually distinguished in traditional practice but is now understood to have a pharmacological profile that is, in key respects, opposite to yohimbine. Research trajectory: Corynanthine is the C-3 diastereomer of yohimbine and an alpha-2 adrenoceptor partial agonist — meaning it can both mildly activate and block alpha-2 receptors depending on context. This paradoxical pharmacology compared to yohimbine (a pure antagonist) makes corynanthine an interesting pharmacological tool compound and modulator of the full yohimbe alkaloid complex’s net adrenergic effect. See sourcing options below.

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Evidence for Corynanthine Applications

Alpha-2 adrenoceptor partial agonism: Corynanthine binds alpha-2 adrenoreceptors as a partial agonist — it has lower intrinsic activity than the endogenous agonist noradrenaline, so it acts as a functional antagonist in the presence of full agonists (blocking noradrenaline) but as a mild agonist in the absence of strong agonist stimulus. This partial agonist profile means corynanthine produces less cardiovascular stimulation than yohimbine at equivalent receptor occupancy. Claim strength: Moderate (mechanism well-characterised; human data limited).

Antihypertensive effect: In animal studies, corynanthine produces antihypertensive effects via CNS alpha-2 partial agonism (similar to the mechanism of clonidine, a pharmaceutical antihypertensive), contrasting sharply with yohimbine’s hypertensive tendency. This makes corynanthine a pharmacological moderator of yohimbe extract’s cardiovascular effects. Claim strength: Moderate (preclinical).

Modulation of yohimbe extract profile: The co-presence of corynanthine in whole yohimbe bark extract may attenuate some of yohimbine’s cardiovascular stimulant effects, contributing to the observation that crude yohimbe bark extract sometimes shows a different cardiovascular profile than isolated yohimbine HCl at equivalent yohimbine doses. Claim strength: Moderate.

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Dosage & Formulator Specification

Corynanthine is not a standalone supplement ingredient. In yohimbe bark extract, corynanthine constitutes approximately 5–15% of total alkaloids alongside yohimbine as the dominant alkaloid. Its co-presence in whole yohimbe extract is a pharmacological consideration for understanding the full extract’s safety profile relative to isolated yohimbine.

For formulators choosing between whole yohimbe bark extract and isolated yohimbine HCl: the whole extract delivers corynanthine and other alkaloids that may modulate the net cardiovascular response. Isolated yohimbine HCl provides pure alpha-2 antagonism without corynanthine modulation. The safety and regulatory implications of this distinction should be considered in formulation design.

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Frequently Asked Questions — Corynanthine

Is corynanthine the opposite of yohimbine?
Functionally yes — yohimbine is a pure alpha-2 antagonist (blocks alpha-2 receptors, increases noradrenaline); corynanthine is an alpha-2 partial agonist (mildly activates alpha-2 receptors in the absence of full agonists, reducing sympathetic output). The result is that the two alkaloids partially counteract each other’s cardiovascular effects in whole yohimbe bark extract, potentially explaining why crude yohimbe extract can have a different risk profile than isolated yohimbine.

Does corynanthine have any erectile function activity?
The alpha-2 partial agonist profile means corynanthine does not share yohimbine’s pro-erectile alpha-2 antagonism. At low concentrations, corynanthine may actually mildly impair the vasodilatory response that yohimbine promotes. This is consistent with the observation that some whole yohimbe bark extracts have weaker pro-erectile activity than isolated yohimbine at equivalent total alkaloid doses.

Is corynanthine relevant to the body composition effects of yohimbe?
Corynanthine’s alpha-2 partial agonism would reduce the lipolytic effect that yohimbine’s pure alpha-2 antagonism produces in adipose tissue. This is a pharmacological argument for preferring isolated yohimbine HCl over whole bark extract for body composition applications where maximum alpha-2 receptor antagonism in adipose tissue is the intent.

Is corynanthine found in any other plant besides yohimbe?
Corynanthine is also present in Rauwolfia species (Indian snakeroot, sarpagandha) alongside reserpine and other indole alkaloids. The Rauwolfia alkaloid complex is pharmacologically complex for the same reason as yohimbe — co-present alkaloids with partially antagonistic pharmacological profiles. Corynanthine from Rauwolfia sources is identical to that from yohimbe.

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Claim-strength scale – High = multiple human RCTs; Moderate = limited trials or strong preclinical convergence; Emerging = early-stage lab or animal data.

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