# Okomu (Rauvolfia vomitoria)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/okomu-rauvolfia-vomitoria
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-04-02
**Evidence Score:** 1 / 10
**Category:** African
**Also Known As:** Rauvolfia vomitoria Afzel., Okomu, Swizzle stick, African serpentwood, Poison devil's pepper, Akanta (Igbo), Luvuwo (Kikongo)

## Overview

Rauvolfia vomitoria contains squalene, phytol, n-hexadecanoic acid, cis-vaccenic acid, and flavonoid-rich phenolic compounds that exert antioxidant, MAO-inhibitory, and putative antihypertensive effects through [free radical scaveng](/ingredients/condition/antioxidant)ing and lipid-modulating pathways. Preclinical phytochemical analyses and in vitro studies demonstrate significant radical scavenging and monoamine oxidase inhibition from methanolic and ethanolic leaf extracts, though no human clinical trial data currently quantifies antihypertensive effect sizes in standardized doses.

## Health Benefits

- **Antihypertensive Activity**: Traditional Yoruba use targets elevated [blood pressure](/ingredients/condition/heart-health), and the plant's fatty acid and phenolic constituents are hypothesized to reduce vascular oxidative stress; however, controlled human trial data confirming blood pressure reduction is currently absent.
- **[Antioxidant Protection](/ingredients/condition/antioxidant)**: Methanolic leaf extracts demonstrate superior radical scavenging activity compared to aqueous extracts (p≤0.05), driven by high flavonoid concentrations of 7.99–9.43 mg/g dry weight phenolics and significant tannin content (5.37 mg/g).
- **[Neuroprotective](/ingredients/condition/cognitive) Potential**: Ethanolic leaf extracts inhibit both monoamine oxidase (MAO) and cholinesterase enzymes in vitro, mechanisms relevant to neurodegenerative conditions such as Alzheimer's disease and age-related cognitive decline.
- **[Antimicrobial](/ingredients/condition/immune-support) Activity**: GC-MS-identified compounds including n-hexadecanoic acid and squalene from leaf and root extracts exhibit in vitro antimicrobial properties against bacterial and fungal pathogens, supporting ethnomedicinal use in wound care and infectious disease.
- **[Hepatoprotective](/ingredients/condition/detox) Effects**: Phenolic constituents and squalene in leaf extracts are associated with hepatoprotective activity, reducing lipid peroxidation in hepatic tissue models and potentially attenuating chemically induced liver damage.
- **Hypocholesterolemic Support**: The high proportion of n-hexadecanoic acid (palmitic acid) and cis-vaccenic acid in root extracts, alongside squalene, contributes to preclinical evidence suggesting modulation of lipid [metabolism](/ingredients/condition/weight-management) and cholesterol biosynthesis pathways.
- **Antidiabetic Traditional Use**: African ethnomedicinal traditions document use of R. vomitoria for managing diabetes mellitus, with phenolic antioxidants hypothesized to reduce oxidative stress-driven pancreatic beta-cell damage, though in vivo mechanistic data remains sparse.

## Mechanism of Action

The flavonoid and phenolic constituents present in methanolic and ethanolic leaf extracts act as electron donors that directly scavenge hydroxyl radicals, superoxide anions, and peroxyl radicals, interrupting oxidative chain reactions associated with vascular and neuronal damage. These phenolics additionally inhibit Fe²⁺-induced [lipid peroxidation](/ingredients/condition/antioxidant) by chelating catalytic iron ions, thereby reducing membrane lipid degradation in neuronal and hepatic cell models. Monoamine oxidase (MAO-A and MAO-B) inhibition by ethanolic leaf extracts limits catecholamine and [serotonin](/ingredients/condition/mood) catabolism, potentially elevating [neurotransmitter](/ingredients/condition/cognitive) availability and contributing to anxiolytic and antidepressant-adjacent effects observed in traditional psychosis management. Squalene, comprising 18.69% of leaf ethanol extract volatiles, functions as a lipid-phase antioxidant and is a known intermediate in the cholesterol biosynthesis pathway, suggesting possible upstream modulation of sterol [metabolism](/ingredients/condition/weight-management), though specific enzyme targets such as HMG-CoA reductase have not been confirmed for this species.

## Clinical Summary

No human clinical trials have been conducted or published for Rauvolfia vomitoria as of the available research context, meaning there are no quantified effect sizes, primary clinical endpoints, or safety data from controlled human studies. Existing studies are restricted to in vitro phytochemical screening and cell-free [antioxidant](/ingredients/condition/antioxidant) assays, which, while supportive of biological plausibility, do not constitute clinical evidence. Traditional use reports in Yoruba, Igbo, and broader West African ethnomedicine document consistent application for hypertension, psychosis, and diabetes, providing a framework for hypothesis generation but not therapeutic validation. Confidence in clinical efficacy remains very low, and translation from in vitro activity to human therapeutic outcomes requires prospective animal toxicology studies, pharmacokinetic profiling, and ultimately phase I–II clinical trials before recommendations can be made.

## Nutritional Profile

Rauvolfia vomitoria leaves and roots are not consumed as a food source and therefore do not contribute meaningfully to macronutrient or micronutrient intake. Key phytochemicals identified by GC-MS in leaf ethanol extracts include squalene (18.69%), phytol (16.47%), and n-hexadecanoic acid (palmitic acid, 15.68%), alongside 9,12,15-octadecatrienoic acid ethyl ester (alpha-linolenic acid derivative, 9.56%) and 7-tetradecenal (Z) (12.90%). Root ethanol extracts are dominated by cis-vaccenic acid (a monounsaturated fatty acid, 32.13%), n-hexadecanoic acid (15.41%), ethyl oleate (10.59%), and smaller proportions of indole alkaloid-related structures. Phenolic content in leaf extracts ranges from 7.99 to 9.43 mg gallic acid equivalents per gram dry weight, with tannins at 5.37 mg/g; flavonoids are enriched in methanolic fractions and contribute to [antioxidant](/ingredients/condition/antioxidant) capacity. Bioavailability of these constituents from crude preparations is unknown, as no pharmacokinetic absorption studies have been conducted in animals or humans.

## Dosage & Preparation

- **Traditional Aqueous Decoction (Leaves)**: Leaves are boiled in water and the decoction consumed orally; aqueous extracts yield approximately 18.8% by weight and contain measurable phenolics (7.99–9.43 mg/g dry weight), though no standardized volume or frequency is established.
- **Traditional Aqueous Decoction (Roots)**: Roots are similarly prepared as decoctions for hypertension and mental disorders in Yoruba practice; root bark is sometimes combined with leaves for synergistic effect in traditional formulations.
- **Ethanolic Extract (Research Standard)**: Ethanol extracts of leaves yield approximately 6.0% by weight and are used in phytochemical studies; no capsule or tablet dosage has been established for human use.
- **Methanolic Extract**: Methanolic leaf extracts demonstrate the strongest [antioxidant](/ingredients/condition/antioxidant) and enzyme inhibitory activity in vitro and are used in laboratory standardization; not currently available as a commercial supplement form.
- **Standardization**: No pharmacopoeial standardization for squalene, phenolic, or flavonoid content exists for this species; no clinically validated effective dose range has been established in human subjects.
- **Timing**: Traditional preparations are typically consumed once or twice daily as a warm decoction; no pharmacokinetic data supports specific timing recommendations relative to meals or other medications.

## Safety & Drug Interactions

Formal human safety data for Rauvolfia vomitoria does not exist in the published literature; no clinical adverse event profiles, maximum tolerated doses, or systematic toxicology studies in humans have been reported, making definitive safety characterization impossible at this time. The related species Rauwolfia serpentina contains reserpine, a potent antihypertensive alkaloid associated with severe depression, bradycardia, nasal congestion, and gastrointestinal disturbances, but R. vomitoria has not been confirmed to contain reserpine and its alkaloid profile differs; direct extrapolation of serpentina safety data to vomitoria is pharmacologically unwarranted without chemical confirmation. Theoretical drug interactions include additive hypotensive effects if co-administered with antihypertensive medications (ACE inhibitors, calcium channel blockers, beta-blockers), and MAO inhibitory activity in vitro raises a theoretical concern for serotonergic or tyramine interactions if MAO inhibition is confirmed in vivo at therapeutic concentrations. Pregnant and lactating women should avoid use given the complete absence of reproductive toxicology data; individuals on psychiatric medications, antihypertensives, or anticoagulants should not use this plant without medical supervision.

## Scientific Research

The current evidence base for Rauvolfia vomitoria consists exclusively of in vitro phytochemical analyses and GC-MS characterization studies, with no published randomized controlled trials, cohort studies, or formal human pharmacokinetic investigations identified in peer-reviewed literature as of the available research context. GC-MS studies have characterized 22 volatile compounds in leaf ethanol extracts and 16 in root extracts, with a separate root analysis identifying 57 compounds, establishing compositional baselines but not efficacy endpoints. In vitro [antioxidant](/ingredients/condition/antioxidant) assays using DPPH and ABTS radical scavenging methods confirm concentration-dependent activity from methanolic leaf extracts, which outperform aqueous fractions at statistically significant levels (p≤0.05), and enzyme inhibition assays confirm MAO and cholinesterase suppression. The overall evidence quality is low by clinical standards; all findings are preclinical, sample sizes in biological assays are not reported as human subject numbers, and effect sizes cannot be translated to therapeutic doses without bioavailability and pharmacokinetic data.

## Historical & Cultural Context

Rauvolfia vomitoria has been employed in West and Central African traditional medicine for centuries, with documented use among the Yoruba of Nigeria (as 'Okomu'), the Igbo, and numerous Central African ethnic groups for the management of hypertension, psychosis, febrile illnesses, and snakebite. In Yoruba healing traditions, the plant occupies a role within the practice of traditional herbalism conducted by 'onisegun' (herbalists), where root decoctions are prescribed for elevated [blood pressure](/ingredients/condition/heart-health) and leaf preparations for mental agitation and spiritual protection. The species name 'vomitoria' alludes to emetic properties recognized by early European botanical recorders, and missionary and colonial-era botanical surveys from the 19th and early 20th centuries catalogued its widespread use across the Congo Basin and Gulf of Guinea forest zones. Unlike its pharmacologically better-characterized relative Rauwolfia serpentina — source of the antihypertensive alkaloid reserpine — R. vomitoria has received comparatively limited formal pharmaceutical investigation despite parallel traditional uses, representing a gap in ethnopharmacological translation.

## Synergistic Combinations

In West African ethnomedicine, R. vomitoria leaves are occasionally combined with Allium sativum (garlic) in hypertension preparations, a pairing that may offer additive vasodilatory and [antioxidant](/ingredients/condition/antioxidant) effects through complementary mechanisms — garlic's allicin inhibiting platelet aggregation and squalene from Okomu modulating lipid oxidation. The plant's MAO-inhibitory flavonoids could theoretically complement [adaptogenic herb](/ingredients/condition/stress)s such as Withania somnifera (ashwagandha), which modulates the HPA axis and reduces cortisol, producing broader [neuroprotective](/ingredients/condition/cognitive) coverage, though this combination has not been studied. Co-administration with vitamin C or other exogenous antioxidants may enhance the phenolic-driven radical scavenging activity by regenerating oxidized polyphenol intermediates, a known synergy mechanism for plant polyphenol systems.

## Frequently Asked Questions

### What is Okomu used for in Yoruba traditional medicine?

In Yoruba traditional medicine, Okomu (Rauvolfia vomitoria) is primarily used to manage hypertension, psychosis, and mental agitation, with root and leaf decoctions prepared by traditional herbalists (onisegun). The plant is also applied for diabetes management and febrile illnesses across broader West African ethnomedicine. These uses are well-documented ethnographically but have not yet been validated through controlled human clinical trials.

### Does Rauvolfia vomitoria contain reserpine like Rauwolfia serpentina?

Available phytochemical analyses of Rauvolfia vomitoria using GC-MS have not confirmed the presence of reserpine, the potent antihypertensive alkaloid characteristic of the related species Rauwolfia serpentina. The dominant bioactive compounds identified in R. vomitoria are fatty acids (cis-vaccenic acid, n-hexadecanoic acid), terpenoids (squalene, phytol), and phenolic antioxidants rather than the indole alkaloids prominent in R. serpentina. This distinction is clinically important because reserpine carries significant side effects including depression and bradycardia that may not apply to R. vomitoria.

### What are the main bioactive compounds in Rauvolfia vomitoria leaves?

GC-MS analysis of Rauvolfia vomitoria leaf ethanol extracts identifies 22 compounds, with squalene (18.69%), phytol (16.47%), n-hexadecanoic acid (15.68%), 7-tetradecenal Z (12.90%), and 9,12,15-octadecatrienoic acid ethyl ester (9.56%) as the major constituents. Leaf extracts also contain significant phenolics at 7.99–9.43 mg/g dry weight, tannins at 5.37 mg/g, and flavonoids that are particularly enriched in methanolic fractions. These compounds collectively underpin the plant's in vitro antioxidant, antimicrobial, and MAO-inhibitory activities.

### Is Rauvolfia vomitoria safe to use, and are there known drug interactions?

No formal human safety studies or clinical toxicology data have been published for Rauvolfia vomitoria, making it impossible to establish a confirmed safe dose or comprehensive side effect profile. Theoretical drug interaction concerns include additive hypotensive effects when combined with antihypertensive medications (beta-blockers, ACE inhibitors, calcium channel blockers) and potential serotonergic interactions due to in vitro MAO inhibitory activity. Until clinical safety data is available, use by pregnant women, nursing mothers, or individuals on prescription medications should be avoided without medical supervision.

### What is the evidence strength for Rauvolfia vomitoria's health benefits?

The evidence for Rauvolfia vomitoria's health benefits is currently limited to in vitro phytochemical analyses and cell-free antioxidant assays; no animal in vivo pharmacological studies or human clinical trials have been published in the accessible literature. While GC-MS studies confirm biologically active compound classes and in vitro assays demonstrate statistically significant radical scavenging and enzyme inhibition (p≤0.05), these findings cannot be directly translated to human therapeutic outcomes without pharmacokinetic and clinical data. The ingredient is best classified as having preliminary ethnobotanical and preclinical support, warranting further investigation rather than therapeutic recommendation.

### What is the difference between Rauvolfia vomitoria and Rauwolfia serpentina in terms of traditional use and composition?

While both plants belong to the Apocynaceae family and contain indole alkaloids, Rauvolfia vomitoria is primarily used in West African Yoruba traditional medicine for blood pressure and fever management, whereas Rauwolfia serpentina is the classical Ayurvedic source of reserpine used in modern antihypertensive pharmaceuticals. Rauvolfia vomitoria contains reserpine and related alkaloids but typically in lower concentrations than R. serpentina, and its fatty acid and phenolic profile differs significantly, suggesting distinct phytochemical compositions that may affect efficacy and safety profiles.

### What forms of Rauvolfia vomitoria are available, and does the extraction method affect its antioxidant potency?

Rauvolfia vomitoria is typically available as dried leaf powder, decoctions, and methanolic or aqueous extracts in traditional and supplement markets. Research shows that methanolic leaf extracts demonstrate superior radical scavenging activity compared to aqueous preparations, suggesting that solvent choice significantly impacts antioxidant bioactivity and that concentrated extracts may deliver higher levels of phenolic and fatty acid constituents responsible for antioxidant protection.

### Who should avoid Rauvolfia vomitoria supplementation due to its alkaloid content and mechanism of action?

Individuals taking antihypertensive medications, monoamine oxidase inhibitors (MAOIs), tricyclic antidepressants, or stimulants should avoid Rauvolfia vomitoria due to potential synergistic or antagonistic effects from its reserpine and related alkaloids, which deplete neurotransmitter stores. Pregnant and nursing women should also avoid this ingredient, as alkaloids cross the placental barrier and may affect fetal development, and individuals with a history of depression or peptic ulcers should exercise caution given reserpine's known neuropsychiatric and gastrointestinal side effects.

---

*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
*License: CC BY-NC-SA 4.0 — Attribution required. Commercial use: admin@hermeticasuperfoods.com*