Anamu (Petiveria alliacea L.): A Comprehensive Reference
1. Identity and Botanical Classification
Scientific and Common Names
Petiveria alliacea L., widely known as anamu, is a perennial herb of the family Phytolaccaceae (sometimes placed in the segregate family Petiveriaceae) distributed across the tropical Americas. The accepted binomial is Petiveria alliacea (Phytolaccaceae). Common names vary markedly by region: anamu (Dominican Republic, Puerto Rico), tipi (Brazil), guinea hen weed and garlic weed (Jamaica), mapurite and gully root (Trinidad), apacin (Guatemala), and mucura (Peru). Published synonyms include Mapa graveolens, P. corrientina, P. foetida, P. graveolens, P. hexandria, and P. paraguayensis. The genus name honors the English botanist and apothecary James Petiver.
Morphology and Natural Distribution
Petiveria alliacea is an herbaceous perennial, typically 0.5–1.5 m in height, with alternate, lanceolate leaves (approximately 10–20 cm long) and elongated, slender racemes bearing small white-green flowers. The alternating and elliptical leaves, small bisexual flowers (white, whitish-pink or green) and achene-type fruits are typical of this plant. The plant emits a pronounced alliaceous odor that intensifies when tissues are bruised or crushed. The root system is fibrous and distinctly aromatic.
This plant is native in tropical regions such as the Amazon rainforest, Central and South America, the Caribbean islands and sub-Saharan Africa. It has been widely distributed from Florida and Mexico, through the Antilles, north and coast of Argentina, to Bolivia, Colombia, Peru, and virtually all regions of Brazil, including the Amazon, Northeast, Southeast, and Midwest. The species' tendency to colonize secondary habitats — roadside margins, disturbed forest edges, and areas near human habitation — has contributed to its stable availability across many regions, though intensified commercial harvesting can exert localized pressure.
Plant Parts Used
Leaves, stems, and roots are all used medicinally. Roots are considered stronger than aerial parts. Most studies of this plant have focused on its roots and on medical-pharmacological applications.
2. Traditional and Historical Use
Overview and Time Period
Petiveria alliacea has been employed in traditional medicine throughout the Caribbean and South America for centuries, particularly as teas or decoctions to alleviate colds, flu, fever, and inflammation. The use of this species for religious ceremonies has been reported since the era of slavery in the Americas.
Uses by Region and Culture
Among Indigenous and mestizo groups, anamu is used in energetic purification (limpieza) and for infections, fever, inflammation, and pain, with roots and aerial parts prepared as baths, washes, smudges, and short-course decoctions. In Jamaica and other Caribbean islands, where it is called guinea hen weed, the plant is frequently used to treat headaches, respiratory issues, and general infections through infusions of leaves or roots.
Popularly known by several different names including mucuracaá, guiné, and pipi, P. alliacea has been used in traditional medicine for the treatment of various central nervous system (CNS) disorders, such as anxiety, pain, memory deficits, and seizures, as well as for its anaesthetic and sedative properties.
A decoction of the roots is used in the Amazonian region as an abortifacient, antispasmodic, analgesic, sudorific, and antirheumatic. The entire plant, leaves, and roots are often used in decoctions to calm the nerves, control diarrhoea, lower fever, stimulate the uterus, and relax spasms. The plant is also used in the treatment of hysteria, paralysis, bronchial problems (asthma, whooping cough, pneumonia, and bronchitis).
Contemporary surveys indicate increased regional use in integrative and phytotherapeutic contexts in Peru, Brazil, Colombia, and Cuba, where anamu occupies a liminal position between folk medicine and formal phytotherapy. Its incorporation into syncretic ceremonies — including house cleansings, altar work, and offerings — extends to contexts such as despacho rituals in Andean-influenced practice, where aromatic plants are assembled to restore balance and protection.
The ethnobotanical uses of P. alliacea include the treatment of respiratory disorders, fever, venereal diseases, and influenza. The nutritional uses include the use of the powder as herbal concoctions in the form of extracts, teas, and capsules.
3. Key Phytochemical Constituents
Organosulfur Compounds
Most prominent among the constituents are sulphur compounds (similar to allicin, found in garlic and onion), flavonoids, triterpenes, steroids, saponins, polyphenols, fredelinol, pinitol, and allantoin. Pentane extracts of the roots have revealed the presence of several volatile constituents such as benzaldehyde (48.3%), dibenzyl-disulfide (23.3%), dibenzyl-trisulfide (9.4%), and stilbene (8.1%). The inflorescences contain benzaldehyde (54.8%), benzylthiol (20.3%), and dibenzyl-disulfide (18.0%).
Root chemical analyses have revealed coumarins, benzyl-hydroxy-ethyl-trisulphide, benzaldehyde, benzoic acid, dibenzyl trisulphide, potassium nitrate, β-sitosterol, isoarborinol, isoarborinol-acetate, isoarborinol-cinnamate, polyphenols, trithiolaniacine, glucose, and glycine.
Flavonoids and Phenolics
Compounds isolated from P. alliacea include astilbin, myricitrin, and engeletin (flavonoids), triterpenes, daucosterol, and lignoceric acid. Additional reports confirm the presence of flavonoids, terpenoids, tannins, phenols, alkaloids, carotenoids, and sulfur-containing compounds like dibenzyl-disulfide and dibenzyl-trisulfide. The consistent detection of phenolic compounds, such as isoarborinol, myricetin, and quercetin, supports the extract's antioxidant potential.
Dibenzyl Trisulfide (DTS): The Principal Active Compound
Dibenzyl trisulfide (DTS) is the major active ingredient expressed in Petiveria alliacea L., a shrub widely used for a range of conditions, such as arthritis, asthma, and cancer. Compounds isolated from extracts (water, methanol, ethanol) of the entire plant include dibenzyl-trisulfide, benzaldehyde, the benzopyran astilbin, and coumarin which, based on in vitro studies, have retarded the growth of leukaemia cells and several other cancer lines.
Along with flavonoids, steroids, and triterpenes, P. alliacea also has sulfur-containing compounds like sulfides, polysulfides, and sulfoxides that make it unique. Leaf extracts contain flavonoids and tannins which work as antidiabetic and antioxidant agents. In addition, other compounds found in P. alliacea leaf extracts like linoleic acid and allantoin may play a role in insulin secretion.
4. Mechanisms of Action
Anti-inflammatory Pathways
Oral administration of P. alliacea root extract to rats resulted in reduced migration of neutrophils, mononuclear cells, and eosinophils to the site of inflammation, thereby exerting an anti-inflammatory effect. In in vitro macrophage models, the ethanol extract from P. alliacea was investigated for anti-inflammatory effects through evaluating production of several cytokines, chemokines, and expression of nuclear factor-kappa B (NF-κB) in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages.
Immunomodulatory Mechanisms
Dendritic cells (DC) promote adaptive immune response by activating T lymphocytes. In a study evaluating immunomodulatory activity of aqueous and organic plant fractions from P. alliacea using human monocyte-derived dendritic cells, the phenotype, cytokine secretion, and gene expression were estimated after treatment with the plant fractions. The aqueous fraction was found to induce morphological changes and co-stimulatory expression of CD86, indicating partial DC maturation. Pro-inflammatory cytokines such as IL-1β, IL-6, IL-8, IL-10, IL-12p70, and TNF-α were secreted. The fraction also increased NF-κB gene expression while down-regulating TGFβ gene expression.
DTS has been previously reported to exhibit potent immunomodulatory function, capable of increasing murine thymic weight along with up-regulation of parameters associated with the reticuloendothelial system, a system essential for molecules involved in immunomodulatory functions.
Anticancer and Cytotoxic Mechanisms
Dibenzyl trisulphide, one of the active ingredients of Petiveria alliacea, causes disassembly of microtubules in neuroblastoma cells resulting in inhibition of cell proliferation. The anamu extract regulates energetic metabolism by altering the expression of enzymes involved in glycolysis, decreasing glucose uptake, and increasing lactate secretion. It also alters βF1ATPase expression, decreasing mitochondrial respiration and intracellular ATP levels.
DTS, the main byproduct of P. alliacea, has been shown to stop HIV-1 reverse transcriptase.
CYP450 Enzyme Inhibition
Given its use alone and concomitantly with prescription medicines, investigators undertook to study its impact on the activities of important drug metabolizing enzymes, the cytochromes P450 (CYP). DTS revealed significant impact against the activities of CYPs 1A2, 2C19, and 3A4 with IC50 values of 1.9, 4.0, and 3.2 μM, respectively, which are equivalent to known standard inhibitors of these enzymes (furafylline and tranylcypromine), and the most potent interaction with CYP1A2 displayed irreversible enzyme kinetics. The root extract drawn with 96% ethanol (containing 2.4% DTS), displayed IC50 values of 5.6, 3.9, and 4.2 μg/mL, respectively, against the same isoforms, CYPs 1A2, 2C19, and 3A4.
5. Scientific Evidence by Area of Use
5.1 Anti-inflammatory and Analgesic Effects
Preclinical evidence for anti-inflammatory and analgesic properties is relatively consistent. Multiple animal model experiments have demonstrated reduced inflammatory markers, edema, and pain responses in rodents administered P. alliacea extracts. No toxic effects were observed in antiedematogenic experiments, and the test extract showed evident antiedematogenic activity. It is understood that the inhibition of edema induced by venom was obtained by reducing the pathways of the inflammatory cascade, giving traditional use some scientific basis.
Human/clinical evidence is limited and, where it exists, is negative. Although petiveria extract exhibited anti-inflammatory and analgesic effects in animals, it did not show any benefits in patients with osteoarthritis compared with placebo. A small study done in patients with osteoarthritis did not show benefits of P. alliacea compared with placebo. Laboratory studies showed that P. alliacea can be toxic to some cancer cells, but more data is needed. Overall, the evidence in humans for anti-inflammatory and analgesic indications is currently insufficient to support efficacy claims.
5.2 Antimicrobial Activity
In vitro, extracts of this herb demonstrated antimicrobial, antifungal, antiviral, antiprotozoal, and immunomodulatory properties. The herb is rich in sulfur-containing compounds that possess a broad-spectrum of in vitro antimicrobial activity against pathogenic fungi and bacteria at low concentrations. A total of eighteen organosulfur compounds from the roots have been tested for their antibacterial and antifungal activities. Investigations have evaluated the antibacterial activity of P. alliacea crude extract and fractions against Staphylococcus aureus and Escherichia coli. To quantify astilbin and engeletin, a method based on HPLC coupled to a diode array detector (DAD) was developed. The P. alliacea crude extracts and fractions exhibited MIC values ranging from 10 to 25 mg/mL.
Evidence strength: All published antimicrobial evidence is in vitro or animal-based. No controlled human trials of anamu for infectious disease endpoints have been reported. The MIC values documented (10–25 mg/mL) are relatively high for practical therapeutic application.
5.3 Anticancer Activity
P. alliacea showed cytotoxicity and antiproliferative activity against cancer cell lines through sophisticated machinery of cellular damage in vitro. The cytotoxic activity of the ethanolic extract against leukemia cells is not very high, but it was possible to evidence its antitumor activity against various leukemic cell lines such as K562, HL60MX, NB4, SUP-B15, Jurkat, U937, and RS4 when the secondary metabolites of the plant are concentrated in organic extracts of ethyl acetate.
There is ethnopharmacological evidence that Petiveria alliacea can have antitumor activity; however, the mechanism of its cytotoxic activity is not well understood. Multiple in vitro biological activities of an ethyl acetate soluble plant fraction were assessed over several tumor cell lines using tests including trypan blue exclusion, MTT assay, flow cytometry, cytoskeleton organization analysis, cell cycle evaluation, mitochondria membrane depolarization, clonogenicity, DNA fragmentation, and differential protein expression by HPLC-Chip/MS analysis.
Data on its cytotoxic effects are conflicting. As of the most recent literature, a published human study protocol exists: Ballesteros-RamÃrez et al. describe exploring the safety and efficacy of phytomedicine Petiveria alliacea extract (Esperanza) in patients with metastatic gastrointestinal tumors and acute leukemias in a Phase Ib/randomized double-blind Phase II trial (PA001), published in BMC Complement. Med. Ther. 2023 Aug; 23(1): 284. This study protocol represents one of the first formal attempts to test anamu in cancer patients, and results were not yet published at the time of this writing.
Evidence strength: Anticancer evidence is predominantly in vitro and in animal models. Laboratory studies showed that P. alliacea can be toxic to some cancer cells, but more data is needed. It has not been studied sufficiently in humans.
5.4 Immunomodulatory Effects
One study provides evidence for possible immunomodulatory activity of P. alliacea extracts using human monocyte-derived dendritic cells, a preparation used in traditional medicine in Colombia. This is cell-based human-derived research, but not a clinical trial. Results suggest that the aqueous fraction can induce partial DC activation, a situation that can be relevant in tolerance induction. The organic fraction by itself did not show immunomodulatory activity.
Evidence strength: Preclinical and cell-based; no randomized controlled human trials on immune outcomes have been completed.
5.5 Central Nervous System Effects (Anxiolytic, Sedative, Anticonvulsant, Cognitive)
The available data reviewed in a comprehensive 2016 PubMed-indexed review support the emergence of P. alliacea as a potential source for the treatment of different CNS disorders including anxiety, depression, pain, epilepsy, and memory impairments. Crude extracts of P. alliacea have been shown to exhibit various neuropharmacological benefits including cognitive enhancing activity, as well as anxiolytic, antidepressant, antinociceptive, and anti-seizure properties in preclinical models.
The whole plant extracts have anxiolytic effects, whereas an extract of aerial parts showed anxiogenic properties, and root extracts showed anticonvulsant effects in mice. This conflicting directionality of CNS effects depending on plant part and extract type is a notable feature of the literature.
Further studies are certainly required to improve the knowledge about the mechanisms of action, toxicity, and efficacy of the plant as well as its bioactive compounds before it can be approved in terms of its safety for therapeutic applications.
Evidence strength: All CNS evidence is from animal or in vitro studies. No human trials have evaluated any neurological or psychiatric endpoints.
5.6 Hypoglycemic and Antidiabetic Effects
The combined phytochemical and pharmaceutical study of Petiveria alleaceae L. (anamú) has shown the existence in the leaves and stems of the plant of a possible hypoglycemic active principle. Extracts from leaves and stem powder were found to produce a decrease of blood sugar concentration of more than 60% one hour after oral administration in male Balb/C mice weighing 20 g fasted for 48 hours.
In a more recent animal study, the hypoglycemic and antioxidant effect of P. alliacea was investigated on streptozotocin-induced diabetic rats, divided into groups receiving normal control, diabetes control, metformin (150 mg/kg/d), and low (90 mg/kg/d), intermediate (180 mg/kg/d), and high (360 mg/kg/d) doses of P. alliacea.
Evidence strength: Hypoglycemic effects have been demonstrated in rodent models only. No human clinical trials have examined blood glucose outcomes with anamu.
6. Dosage Forms and Reported Preparations
The traditional remedy calls for a decoction or infusion prepared with 30 grams of dried anamu whole herb in a liter of water; ¼ cup to ½ cup dosages are taken one to three times daily or used topically, depending on the condition treated. Since most of the chemicals are water soluble, powdered whole herb in tablets or capsules (1–3 grams) daily can be substituted.
In North American herbal medicine systems for menstrual difficulties, the remedy is generally 1–2 g of the powdered vine in tablets or capsules two or three times daily, or 2–3 ml of a standard tincture twice daily, or as needed.
The leaves, stems, and roots of anamu have been traditionally taken as tea or tincture to treat infections, headaches, fever, and cold. It is topically applied for skin fungal infections and to heal cuts and wounds. Anamu is available over the counter in the United States as dried roots and leaves, and as extracts in capsules and tablet forms.
It is important to note that no standardized dose has been established through controlled clinical trials. Since dosage has not been well established, using it incorrectly may lead to toxicity.
7. Safety Considerations and Drug Interactions
Acute vs. Chronic Toxicity
In an overview, the acute toxicity of this plant in animal models (up to 14 days) was found to be low. However, in chronic and subchronic exposure, P. alliacea was able to induce moderate to high toxicity, including mutagenicity and genotoxicity.
Genotoxicity and Mutagenicity
Genotoxic activities of anamu have been investigated using a sister chromatid exchange (SCE) assay using cells in vitro and in vivo. Lymphocytes from humans were treated at 24 h after initiation of culture for 6 h with alcohol extract. Concentrations of 0, 10, 100, 250, 275, 500, 750, and 1000 μg/ml of the extract were used. Significant dose-dependent increase of SCE (3.7–7.4 SCE per cell) were observed.
Mutagenic and carcinogenic effects have been reported: Hoyos et al. (1992) demonstrated the dose-dependent mutagenic and carcinogenic effect of P. alliacea extract. They reported DNA damage with the formation of sister chromatid exchanges (SCEs) in human lymphocytes in vitro and in mouse bone marrow cells in vivo, especially at higher concentrations of 100 and 1000 μg/ml (in vitro) and 204 mg/kg (in vivo).
The micronucleus assay showed that a hydroethanolic extract of P. alliacea (EHPa) induced slight genotoxicity in vivo. However, EHPa induced an exacerbated DNA damage in vitro, but this effect was slight in the animal model.
The results of yeast cell assays indicate that fractions of mid-polarity of the ethanolic extract, at the studied concentrations, can induce mutagenicity mediated by oxidative lesions in the mitochondrial and genomic genomes. These findings indicate that the lesions caused by the fractions of P. alliacea ethanolic extract can be mediated by reactive oxygen species and can reach multiple molecular targets to exert their toxicity.
In vitro and in vivo assays showed that petiveria has mutagenic effects.
Uterine Stimulant and Reproductive Risks
Safety considerations include potential side effects such as nausea when consumed in high doses, and it is contraindicated during pregnancy due to its emmenagogue properties that may stimulate uterine contractions. The traditional use of anamu root as an abortifacient in the Amazon Basin (documented in ethnobotanical texts) is consistent with this risk profile.
Hypoglycemic Risk
Animal studies have shown that P. alliacea has a hypoglycemic effect, so individuals with hypoglycemia or diabetes should be aware of its use. In vitro and in vivo studies of Petiveria alliacea extracts on behavioural stress in animal models revealed a pro-oxidant effect which resulted in inhibition of the antioxidant level and increased methemoglobin levels in human plasma, which may have important implications for anxiety-like behaviour.
CNS Effects and Neurological Risk
Most studies confirmed the diverse acute effects of P. alliacea on the CNS, including anxiety, restlessness, confusion, ataxia, tremors, and seizures in animal studies at significant doses.
Drug–Herb Interactions: CYP450 Inhibition
DTS revealed significant inhibitory impact against CYPs 1A2, 2C19, and 3A4 with IC50 values of 1.9, 4.0, and 3.2 μM, respectively. The root extract drawn with 96% ethanol (containing 2.4% DTS) displayed IC50 values of 5.6, 3.9, and 4.2 μg/mL against the same isoforms. These investigations identify DTS as a valuable CYP inhibitor and P. alliacea as a candidate plant worthy of clinical trials to confirm that extracts yielding high DTS may lead to clinically relevant drug interactions, whilst extracts yielding low levels of DTS, such as aqueous extracts, are unlikely to cause adverse herb-drug interactions.
Potential mutagenic effects have been observed in laboratory and animal studies, and it may interact with antidiabetic drugs and medications metabolized by CYP450 enzymes (such as CYP1A2, 2C19, and 3A4). These interactions are documented in vitro but have not been confirmed in clinical pharmacokinetic studies in humans.
Due to anamu's natural coumarin content, it is conceivable that it may potentiate the effects of anticoagulant drugs, though this has not been formally studied.
Overall Safety Profile
In folk medicine, Petiveria alliacea has a broad range of therapeutic properties; however, it is also associated with toxic effects. The genotoxicity signals from both in vitro and in vivo studies, the documented uterotonic properties, the potential for CYP450-mediated drug interactions, and the blood sugar-lowering effects documented in animal models represent the most clinically relevant safety concerns identified in the peer-reviewed literature. Human safety data are scarce, and formal toxicology studies in humans have not been conducted.
8. Body Systems and Areas of Research Interest
- Immune System: In vitro, extracts of this herb demonstrated antimicrobial, antifungal, antiviral, antiprotozoal, and immunomodulatory properties.
- Musculoskeletal / Inflammatory: Used in traditional medicine as an antirheumatic, antispasmodic, antifungal, and analgesic for pain relief. One clinical trial failed to find benefit over placebo in osteoarthritis.
- Oncology: Antitumor activity demonstrated against various leukemic cell lines such as K562, HL60MX, NB4, SUP-B15, Jurkat, U937, and RS4. No completed human trials.
- Central Nervous System: The available data support the emergence of P. alliacea as a potential source for the treatment of different CNS disorders including anxiety, depression, pain, epilepsy, and memory impairments — all preclinical evidence only.
- Endocrine / Metabolic: Hypoglycemic effects in rodent models; potential interaction with antidiabetic drugs.
- Reproductive System: Traditional use as a uterine stimulant and abortifacient; contraindicated in pregnancy.
- Respiratory: Traditional use for asthma, bronchitis, and coughs; no clinical evidence available.
- Integumentary: Topical use for skin fungal infections and wound healing documented in traditional systems.
9. Evidence Summary
Many traditional uses of P. alliacea have now been validated by modern pharmacology research at the preclinical level, but the translation to human clinical evidence remains in early stages. The breadth of activity documented in vitro and in animal models — antimicrobial, anti-inflammatory, immunomodulatory, cytotoxic, hypoglycemic, and CNS-active — is striking, but no indication has been confirmed in adequately powered, well-designed human randomized controlled trials. The one published human clinical trial (osteoarthritis) produced a null result. A Phase II cancer trial protocol was published in 2023, representing the most advanced clinical investigation to date. Further studies are certainly required to improve the knowledge about the mechanisms of action, toxicity, and efficacy of the plant as well as about its bioactive compounds before it can be approved in terms of its safety for therapeutic applications.
References
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