IngredientsScientific name: Jatropha macrantha Müll. Arg. The species epithet honors the size of its flowers; the author citation "Müll. Arg." refers to Johannes Müller Argoviensis, the Swiss botanist who formally described the taxon.
Family: Huanarpo Macho (Jatropha macrantha) is a member of the Euphorbiaceae family.
Common names: Jatropha macrantha, also called the huanarpo macho, is a medium-size shrubby tree species in the genus Jatropha with orange-red flowers. In popular marketing contexts it has been called "Peruvian Viagra" and "Peruvian Ginseng," though these are informal commercial designations rather than established pharmacopeial names.
Genus context: The Euphorbiaceae family is represented by about 8,100 species and 300 genera, distributed in tropical and subtropical regions. Within this family, several useful species — particularly the genera Croton, Euphorbia, and Jatropha — are used as medicinal plants. Currently, more than 80% of Jatropha genus species are used in folk medicine from Africa, Asia, and Latin America. Moreover, this genus has more than 175 species and its members are recognized as important sources of secondary metabolites with a broad spectrum of biological functions.
Morphology and geographic range: Jatropha macrantha is a wild and endemic shrub of Peru, reaching 1–2 meters in height. It grows in the Marañón river valley (high rainforest) and in the towns of Ancash, Arequipa, Cajamarca, Huánuco, La Libertad, and Puno (high Andean areas).
Plant parts used and common forms: Of all the bush, only the root and its tubers are used — the underground part — with parts of the root in conjunction with the tubers acquiring the shape of a penis. Traditionally, the bark and roots of Jatropha macrantha were prepared as decoctions or infusions, believed to invigorate the body and support vitality. In contemporary commerce the plant is sold as dried and powdered stems or roots, alcoholic tinctures, and standardized extracts.
Botanical authentication: Leaves and stems of J. macrantha used in published research were collected in Sacrapa of the province of Paucarcocha, Peru. The botanical identification was carried out in the Natural History Museum of the Universidad Nacional Mayor de San Marcos.
Jatropha macrantha, commonly known as "huanarpo macho," is a plant native to Peru and has a long-standing history of use in traditional medicine, particularly as an aphrodisiac and for supporting male reproductive health. Historical records and ethnobotanical surveys document its use by indigenous peoples to increase libido, improve erectile function, and enhance sexual performance.
It has been used since Inca times for problems of erectile dysfunction (or sexual impotence, to increase sexual arousal), premature ejaculation, or as a restorer of sexual potency for middle-aged men and seniors, and additionally as a powerful energizer.
The traditional application involves preparing decoctions or extracts from the stem and bark, which are consumed for their reputed benefits on male vitality.
Beyond sexual health, broader traditional applications have been attributed to the plant in Peruvian herbal medicine. J. macrantha is considered a sexual stimulant, antiasthmatic, antidiabetic, antitussive, and antiulcer agent. The branches and/or bark of the tree are also used in Peruvian herbal medicine for asthma, bronchitis, cough, and diabetes.
Huanarpo macho is a plant that follows what is termed in botany and ethnobotany the "Doctrine of Signatures." This doctrine is based on the observation that one can determine — from the color of the flowers or roots, the shape of the leaves, the place of growing, or other "signatures" — what the plant should be used for. The young branch stems of the huanarpo macho tree are shaped like a man's anatomy, and for centuries these young branch stems have been used in traditional medicine systems to support, aid, and enhance male sexual function.
Both L. meyenii (maca) and J. macrantha have been widely used as folk medicines in Peru and have been administered to treat impotence, climacteric disorders, and infertility in Europe and America. Huanarpo macho is frequently combined with other Peruvian botanicals. In the context of herbal combinations, Jatropha macrantha is frequently blended with other South American botanicals such as Lepidium meyenii (maca) and Erythroxylum coca to create synergistic formulas aimed at improving stamina, mood, and overall vitality.
Jatropha macrantha contains a complex array of secondary metabolites. Published phytochemical investigations have characterized constituent classes from various plant parts using techniques ranging from classical chromatography to modern LC-ESI-MS/MS.
A phytochemical investigation of the methanol extract of the stem of J. macrantha led to the isolation of catechin, catechin-7-O-β-glucopyranoside, and proanthocyanidin B-3, along with other catechin polymers. Their structures were established by NMR and ESI/MS experiments. EGCG (epigallocatechin gallate), proanthocyanidin, and catechin-7-O-β-glucopyranoside have also been detected in J. macrantha.
On the basis of spectrometric data, in J. macrantha stem extract, proanthocyanidins exist with an extremely wide molecular weight range, from 290 (corresponding to catechin) to 3,144 (corresponding to an oligomer generated from the condensation of 11 catechin units), and all intermediate molecular weights are present.
The 2021 LC-ESI-MS/MS study by Tinco-Jayo et al. provided the most detailed phytochemical profiling to date. The leaves extract had 77 phytochemical constituents, of which 25 were observed in ESI(−), 42 in ESI(+), and 10 in both modes; in the stems extract, 42 compounds were determined, of which 18 metabolites were observed in ESI(−), 21 in ESI(+), and 3 in both modes.
The constituent classes identified in the leaves were: flavonoids (21); coumarins and derivatives (11); sesquiterpene lactones and sesquiterpenoids (4); terpene lactones and terpenoids (3); organic acids (3); anthraquinones (2); eudesmanolides and derivatives (2); phytoprostanes (3); phenolic acids (1); and others (27). In the stems: coumarins and derivatives (6); flavonoids (3); sesquiterpene lactones and sesquiterpenoids (3); terpene lactones and terpenoids (3); organic acids (3); aromatic monoterpenoids (2); benzyl alcohols (2); alkyl-phenylketones (2); and others (18).
By chromatography, flavone-like structures were revealed, and by UV spectroscopy and displacement reactions the following compounds were identified in the methanol extract: 6-hydroxy-4,5,7-trimethoxyflavone; 4,7-dihydroxy-5,6-dimethoxyflavone; 7-hydroxy-3,4,5,5,8-pentamethoxyflavone; and 4,7-dihydroxy-3,5,6-trimethoxyflavone.
Three pentacyclic triterpenes — oleanolic acid, azarolic acid, and 3-oxo euscaphic acid — were isolated from the hexane extract of Jatropha macrantha Müll. Arg. (Euphorbiaceae); their structures were elucidated by spectroscopic means.
Scopoletin (a coumarin) was identified among the phytochemical constituents of J. macrantha. Scopoletin showed a positive effect on penile erection of rats through the NO-cGMP pathway. The coumarin class was the second most represented constituent group in the stems fraction in the 2021 study.
A Peruvian researcher attributed the aphrodisiac effect of a tincture of huanarpo macho to its alkaloid content. Within its secondary metabolites, peptides, alkaloids, lignans, flavonoids, phenolic acids, coumarins, and mainly terpenes have been identified.
Total phenolic content (TPC) of the leaf ethyl acetate fraction (LEAF) and stem ethyl acetate fraction (SEAF) were 359 ± 5.21 mg GAE/g and 306 ± 1.93 mg GAE/g, respectively; total flavonoid content in LEAF and SEAF were 23.7 ± 0.80 mg EQ/g and 101 ± 1.42 mg EQ/g, respectively.
Across the genus, investigations of the chemical constituents of Jatropha plants have resulted in the isolation of alkaloids, cyclic peptides, terpenes (monoterpene, sesquiterpenes, diterpenes, and triterpenes), flavonoids, lignans, coumarins, coumarino-lignoids, a non-cyanogenic glucoside, phloroglucinols, ester ferulates, phenolics, deoxypreussomerins, and fatty acids. In the context of phorbol esters — a class of toxicologically relevant diterpene esters found in several Jatropha species — J. macrantha Müll. Arg. and J. integerrima Jacq. have been reported to contain phorbol esters, which would make their oral consumption problematic.
The most extensively studied proposed mechanism for the aphrodisiac and pro-erectile properties of J. macrantha involves modulation of nitric oxide (NO) signaling. In a rat model using oral administration of 300 mg/kg of the plant methanol extract, the frequency of mounts increased by 75% and levels of nitric oxide rose by 85%, while the 200 mg/kg dose resulted in increases of 71.1% and 32.4%, respectively (p <0.05). The authors concluded that the methanolic extract of J. macrantha had a vasorelaxant modulating effect in rats with induced erectile dysfunction, associated with increased nitric oxide levels.
Scopoletin, one of the identified phytochemical constituents, showed a positive effect on penile erection of rats through the NO-cGMP pathway.
Several authors have reported the possible role of proanthocyanidins (condensed tannins) as sexual stimulants, specifically able to correct erectile dysfunctions and infertility. Thus, the high amount of catechin derivatives in J. macrantha is in agreement with the traditional use of this plant as an aphrodisiac.
The anti-inflammatory activity of the three pentacyclic triterpenes isolated from J. macrantha was evaluated by means of inhibition of NF-κB production and activation of Nrf2 against THP-1, HEK001, NIH-3T3, and B16-F10 cell lines. All three compounds had anti-inflammatory activity; however, azarolic acid had a statistically significant higher inhibitory activity of NF-κB production (IC50 1.87–1.98 μM) than the positive control celastrol (IC50 7.41–7.49 μM).
In antioxidant assays, the DPPH, ABTS, and FRAP values in the SEAF were 647 ± 3.27; 668 ± 2.30; and 575 ± 2.86 μmol TE/g, respectively, while LEAF showed 796 ± 3.15; 679 ± 0.85; and 806 ± 3.42 μmol TE/g, respectively.
It is known that cholinergic stimulation of the cavernous nerve leads to increased blood flow within the penis; on the contrary, adrenergic stimulation reduces blood flow, leading to the flaccid state. Multiple mechanisms could be linked to the relaxation of rat penile tissue in J. macrantha.
Animal evidence (preclinical):
The most rigorously designed preclinical study to date (Tinco-Jayo et al., 2022, PMC8746923) used a ketamine-induced erectile dysfunction rat model. Regarding sexual behavior, the leaf fraction (LEAF) showed a better effect in mount frequency, intromission frequency, ejaculation frequency, mount latency, intromission latency, ejaculatory latency, and post-ejaculatory latency than the stem fraction (SEAF). LEAF of J. macrantha at 50 mg/kg showed a better effect on sexual behavior in male rats with erectile dysfunction than SEAF, but not higher than sildenafil. Experimental groups included: negative control; positive control (ketamine at 50 mg/kg/d); sildenafil 5 mg/kg; LEAF at 25, 50, and 100 mg/kg; and SEAF at 25, 50, and 100 mg/kg.
An earlier Peruvian study (Arroyo et al., published in Anales de la Facultad de Medicina) used the methanol extract in a separate rat model. Sexual behavior, nitric oxide concentration, and vasorelaxant effect were determined in isolated rat penis corpus cavernosum, distributed into groups receiving water 10 mL/kg, sildenafil 5 mg/kg, or methanol extract at 100, 200, and 300 mg/kg.
Hormone effects — animal data:
A 2003 study by Oshima, Gu, and Tsukada (published in the Journal of Veterinary Medical Science) investigated the effects of J. macrantha alone and in combination with Lepidium meyenii on sex hormones in mice. The effects of two Peruvian folk medicines, Lepidium meyenii Walp and Jatropha macrantha, on mouse sex steroid hormones and embryo implantation were investigated. Progesterone levels increased significantly in mice that received L. meyenii Walp, while testosterone levels increased significantly in mice that received L. meyenii Walp as well as in those that received both L. meyenii Walp and J. macrantha. However, there were no marked changes in blood levels of estradiol-17β or the rate of embryo implantation.
Important limitation: There is limited scientific research investigating the efficacy of Jatropha macrantha for male reproductive health. Ethnobotanical records indicate that indigenous peoples and traditional healers have used various preparations of Jatropha macrantha bark and roots to enhance sexual potency, libido, and general male vitality. These uses are mostly based on anecdotal evidence and longstanding cultural practices rather than rigorous scientific validation. Scientific studies on Jatropha macrantha are limited. No randomized controlled trials (RCTs) in human subjects have been published as of the current literature record.
In vitro evidence:
Three pentacyclic triterpenes — oleanolic acid, azarolic acid, and 3-oxo euscaphic acid — were isolated from the hexane extract of J. macrantha. Their structures were elucidated by spectroscopic means. The cytotoxicity of the compounds was evaluated against the THP-1, HEK001, NIH-3T3, and B16-F10 cell lines by the XTT assay; all analyzed compounds were less cytotoxic than the positive control (actinomycin D, CC50 0.00797 μM).
This study (published in Revista Brasileira de Farmacognosia, 2021) reported that the anti-inflammatory activity was evaluated by means of inhibition of NF-κB production and activation of Nrf2 of these compounds against THP-1, HEK001, NIH-3T3, and B16-F10 cell lines; all three had anti-inflammatory activity; however, azarolic acid had a statistically significant higher inhibitory activity of NF-κB production (IC50 1.87–1.98 μM) than the positive control (celastrol, IC50 7.41–7.49 μM).
Evidence strength: In vitro only; no in vivo or human replication data published specifically for this isolate from J. macrantha. Results are preliminary.
The extracts of J. curcas, J. gaumeri, J. gossypiifolia, and J. macrantha are reported to be cytotoxic towards melanoma cells, nasopharynx human carcinoma, and Artemia sp. Additionally, published research specifically on J. macrantha has identified anti-melanogenic potential from its triterpenoid constituents in the same 2021 study that characterized azarolic acid and oleanolic acid. Other studies refer to a bronchodilator effect and antimelanogenic and anti-inflammatory properties of J. macrantha. All evidence in this area is from cell culture studies; no clinical data exist.
Antioxidant activity of J. macrantha extracts has been demonstrated in multiple assays. Phytochemical constituents were determined by LC-ESI-MS/MS; the total phenolic compounds and total flavonoids were quantified by Folin-Ciocalteu and aluminum chloride methods, respectively; and antioxidant activity was determined by DPPH, ABTS, and FRAP assays. The antioxidant capacity values reported were substantial (see Section 4.4 above for numeric values). All data are from in vitro assays; whether these translate to clinically meaningful antioxidant effects in humans has not been demonstrated.
Studies refer to a bronchodilator effect of J. macrantha. This corresponds to its traditional use for asthma and bronchitis noted in Peruvian herbal medicine; however, detailed mechanistic studies or clinical data on this application are not available in the primary peer-reviewed literature accessible at this time.
The following dosages are reported only as used in published scientific studies, not as recommendations:
No human clinical dosing data derived from controlled trials are available in the published literature. Traditional preparations involve decoctions or infusions, but standardized doses for human use have not been validated scientifically.
A significant safety concern for the Jatropha genus is the presence of phorbol esters — toxic diterpene esters known as tumor promoters and potent protein kinase C activators. J. macrantha Müll. Arg. and J. integerrima Jacq. have been reported to contain phorbol esters, making consumption of those plant parts problematic. These esters are primarily concentrated in seeds and certain tissues. The extent to which the root/stem preparations traditionally consumed contain active phorbol esters at toxicologically relevant concentrations has not been fully characterized in the available literature.
Species of Jatropha are notably known for their toxic potential, and their toxicity is primarily related to the latex and seed contents. The EFSA Panel on Contaminants in the Food Chain assessed phorbol ester risks in a related species: the available data on absorption of Jatropha phorbol esters after oral ingestion, biotransformation, elimination, and dose-dependent toxic effects are very limited, and only for pigs has a no-observed-adverse-effect level (NOAEL) been established.
Published LD50 data specific to J. macrantha methanol extract in rats: by UV spectroscopy, the LD50 was identified as 1357 mg/kg (in the rat model of the Peruvian study). This figure applies specifically to the methanol extract tested in that study and should not be extrapolated to other preparations.
Despite promising preclinical findings, clinical trials in humans remain limited. The majority of studies have been conducted in vitro or in animal models, and more rigorous, controlled human studies are required to confirm the safety and efficacy of Jatropha macrantha in nutritional applications.
No peer-reviewed studies characterizing pharmacokinetic drug–drug interactions specifically involving J. macrantha preparations in humans have been identified in the published literature. Given the vasorelaxant and NO-potentiating activity documented in preclinical models, theoretical interactions with phosphodiesterase type-5 inhibitors (e.g., sildenafil, tadalafil) or nitrate medications may be mechanistically plausible, but this has not been empirically demonstrated in published studies.
Extracts and isolated compounds from species of this genus have been found to possess properties of cytotoxicity, antimicrobial, antifungal, anti-inflammatory, antioxidant, insecticidal, larvicidal, inhibition of AChE, and toxicity activities. The presence of potentially cytotoxic cyclic peptides and diterpenes across the genus underscores the importance of part-specific and preparation-specific safety characterization for J. macrantha.
Jatropha macrantha has a well-documented ethnopharmacological record in Peruvian traditional medicine, with use spanning at minimum several centuries for male sexual health, respiratory complaints, and general vitality. The phytochemistry is moderately well characterized: catechin-type proanthocyanidins and methoxylated flavones from stems, pentacyclic triterpenes from the hexane extract, and a wide array of coumarins, flavonoids, and terpenes identifiable by LC-ESI-MS/MS. Proposed mechanisms — particularly NO/cGMP-mediated vasorelaxation, proanthocyanidin-driven effects, and NF-κB inhibition by azarolic acid — are supported by in vitro and animal data.
However, the scientific evidence base is almost entirely preclinical. Clinical trials in humans remain limited; the majority of studies have been conducted in vitro or in animal models, and more rigorous, controlled human studies are required to confirm the safety and efficacy of Jatropha macrantha. The presence of phorbol esters in the species represents an unresolved safety question for oral preparations, particularly those derived from seeds or latex. Quality and standardization of commercially available preparations have not been addressed in the published clinical literature. The overall evidence for any human health claim should therefore be characterized as preliminary, with no clinical trial–level proof of efficacy for any indication.
Health conditions that Jatropha macrantha may help support.
Body systems that Jatropha macrantha may help support.
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