Angel's Trumpet (Brugmansia spp.)
1. Identity and Botanical Classification
Taxonomy and Nomenclature
Brugmansia is a genus of seven species of flowering plants in the nightshade family Solanaceae. Linnaeus first classified these plants as part of Datura with his 1753 description of "Datura arborea"; then in 1805, C. H. Persoon transferred them into a separate genus, Brugmansia, named for Dutch naturalist Sebald Justinus Brugmans. The most widely studied and referenced species include Brugmansia suaveolens, B. arborea, B. sanguinea, B. candida, and B. aurea. Historical synonyms include Datura candida (Pers.) Saff., Brugmansia arborea auct. non (L.) Steud., Datura arborea L., and Brugmansia candida Pers.
Their large, fragrant flowers give them their common name of angel's trumpets, adjacent to the nickname devil's trumpets of the closely related genus Datura. Datura species are not to be confused with angel's trumpets, which are placed in the closely related genus Brugmansia. While the two genera share common names and many chemical constituents, a key morphological distinction is that the angel's trumpet flower faces downward while the devil's trumpet (Datura) faces or blooms upward. Additionally, Brugmansia plants are woody trees or shrubs, with pendulous flowers, and have no spines on their fruit, whereas Datura produces spiny fruit capsules.
Physical Description
Brugmansia are large shrubs or small trees, with semi-woody, often many-branched trunks. They can reach heights of 3–11 m (10–36 ft). The leaves are alternately arranged along the stems, generally large, 10–30 cm (4–12 in) long and 4–18 cm (2–7 in) across, with an entire or coarsely toothed margin, and are often covered with fine hairs. The name "angel's trumpet" refers to the large, pendulous, trumpet-shaped flowers, 14–50 cm (6–20 in) long and 10–35 cm (4–14 in) across at the opening. They come in shades of white, yellow, pink, orange, green, or red. Most have a strong, pleasing fragrance that is most noticeable in the evening. Flowers may be single, double, or more.
Geographic Origin and Conservation Status
The genus Brugmansia (Solanaceae), popularly known as "angel's trumpet," is a native of South America. More specifically, consisting of five species and several hybrids, the Brugmansia species originate in the Andes Mountains of South America. All seven species are known only in cultivation or as escapees from cultivation, and no wild plants have ever been confirmed. They are therefore listed as Extinct in the Wild by the IUCN Red List, although they are popular ornamental plants and still exist wild outside their native range as introduced species.
Common Forms and Preparations
The flowers, fruits, stems, and roots of the plant are used, and different chemical compounds have been identified, such as alkaloids, volatile compounds (mainly terpenes), coumarins, flavonoids, steroids, and hydrocarbons. In traditional and folk medicine contexts, the plant has been used in a variety of preparations. Popularly, its dried flowers and leaves are used to treat strong coughs and bronchitis by inhaling its vapor. In the form of juice and/or ointment, it is applied to burns, abrasions, inflammation, hemorrhoids, arthritis, and rheumatism on the affected areas to relieve pain. In the context of poisoning cases, the plant is most commonly ingested as a brewed tea or as raw parts of the plant, particularly the flowers. Smoking of dried leaves has also been reported cross-culturally (see Traditional Use section below).
2. Traditional and Historical Use
South America: Shamanic and Ritual Use
A key study published in Economic Botany (2004) reports the use of Brugmansia species in traditional practices of shamans (curanderos) of the Northern Peruvian Andes. The field study permitted the classification of a number of species and/or hybrids used for both curative and psychotropic activities. There is evidence of a folk systematics in this genus that constitutes a very important phenomenon for its therapeutic-divinatory, phytotherapeutical, and ritual (in initiation and black magic rites) uses.
Brugmansia suaveolens, a plant growing in the tropical lowlands of the Amazon, is used as a shamanic inebriant and as an ayahuasca admixture (Schultes & Raffauf 1992). The shamanic use of Brugmansia is concentrated mainly in the west: along the Andean and Pacific fringe of the continent from Colombia down to southern Peru and the middle of Chile. The Kamsa and Ingano people of the Sibundoy Valley in the Colombian Andes distribute a number of species throughout the Amazon. The present-day Tzeltal Indians of Mexico smoke the dried leaves of B. suaveolens with Nicotiana rustica in order to obtain visions that indicate the cause of various diseases. The Jivaros use Brugmansia in initiation rituals to communicate with the ancestor spirits.
The Putumayo region of southern Colombia is the center of diversity of Brugmansia and the site of domestication of a large number of medicinal cultivars by the Inga, Kamentsá, Quillasinga, and Siona peoples. The hallucinatory and unique morphology of these cultivars, as well as their medicinal and cultural importance, attracted the attention of Harvard Professor Richard Evans Schultes and his students, the "founding fathers" of chemical ethnobotany.
The use of San Pedro, together with additives like Angel's Trumpet (Brugmansia spp.), Jimson-weed (Datura ferox), and tobacco, is still a central part of the curing ceremonies of healers in Northern Peru. This tradition has deep roots: traditional use of medicinal plants in this region dates as far back as the first millennium B.C.
Brugmansia suaveolens is used in folk medicine for therapeutic purposes and in Peruvian religious myths to seek changes in the individual's conscious state.
Colombia and Pre-Columbian Ritual Use
It is reported that the tradition of the Chibcha Indians of Colombia was to administer Brugmansia to wives and slaves of a departed husband or leader, and then bury them with the deceased alive. This practice underlines the plant's longstanding role as a powerful narcotic agent in pre-Columbian funerary rites.
Hawaii
In 1825, Angel's Trumpet (Brugmansia) arrived in Hawaii. It became one of their sacred flowers, called nanahonua, which means "gazing earthward." Hawaiians smoked the leaves to create a hallucinogenic ritual.
Traditional Therapeutic Uses
This plant has been used in traditional medicine in different cultures as a hallucinatory, analgesic, aphrodisiac, nematicide, sleep inducer, and muscle relaxant, as well as a treatment for rheumatism, asthma, and inflammation. Ethnomedical uses reported around the world include its uses to treat pain, insomnia, rheumatism, infections, asthma, inflammation, sores, wounds, abscesses, dermatitis, snakebites, loss of appetite, coughs, and as an aphrodisiac. Distributed in Africa, America, Europe, Australia, and Asia, it has been used traditionally for the treatment of arthritis, sores, pain, inflammation, ulcers, abscesses, dermatitis, wounds, dysmenorrhea, fungal infections of the skin, and as a vaginal antiseptic in white secretions.
Leaves of Brugmansia suaveolens are traditionally applied in northern Peru for treating wounds. Flowers and leaves are used for curing infections, mental weaknesses, and menstrual pain. It is utilized as an aphrodisiac. The stem is applied externally for skin anomalies for rapid healing. Additionally, Kallawaya people in the Bolivian Andes use the plant to lower fever associated with rubella and scarlatina.
3. Key Constituents and Active Compounds
Primary Alkaloids
Brugmansia species are among the most toxic of ornamental plants, containing tropane alkaloids of the type also responsible for the toxicity and deliriant effects of both jimsonweed and the infamous deadly nightshade. All parts of the plant contain significant quantities of tropane alkaloids, including hyoscine (scopolamine), hyoscyamine, and norhyoscine.
A 2020 PMC review of B. suaveolens described a broad secondary metabolite profile: various secondary metabolites identified include apohyoscine, hyoscine, norhyoscine, meteloidine, atropine, noratropine, cuscohygrine, scopoline, tropine, pseudotropine, apoatropine, and meteloidine. Beyond alkaloids, the genus Brugmansia species contain various phytochemicals including alkaloids, steroids, phenolic compounds, terpenes, tannins, anthraquinone glycoside, triterpenes, saponins, and cyanogenic glycosides, with interest in pharmacological and biological activities. A systematic review published in Nutrients (2023) further identified 120 compounds, including alkaloids, flavonoids, terpenoids, steroids, amino acids, aromatics, and aliphatics.
Quantification of Key Alkaloids
The toxic effect of the plant is mainly attributed to atropine and scopolamine; their averages in the flowers are 0.79 ± 0.03 and 0.72 ± 0.05 mg/g of dry plant, respectively. Because Brugmansia is a natural product, tropane alkaloid content can vary widely by species, location, or weather, which can change the proportions and concentrations of scopolamine and atropine present in the leaves and flowers.
Alkaloid Biosynthesis
Hyoscyamine-6β-hydroxylase (H6H, EC 1.14.11.11) is a plant enzyme that catalyses the last two steps in the biosynthesis of the anticholinergic drug scopolamine: the hydroxylation of hyoscyamine to 6β-hydroxyhyoscyamine (anisodamine) and subsequent oxidative ring-closure to the 6,7-β-epoxide. Anisodamine (6β-hydroxyhyoscyamine) is the intermediate in the conversion of hyoscyamine into scopolamine. Scopolamine is the most abundant tropane alkaloid in B. suaveolens and appears to be produced as a response to damage by herbivory, as is common with many secondary metabolites.
4. Mechanisms of Action
Anticholinergic / Muscarinic Antagonism
Scopolamine and atropine act as antagonists at muscarinic acetylcholine receptors, leading to inhibition of the parasympathetic nervous system. This explains their anticholinergic effects, which, in cases of overdose, result in toxic symptoms such as dry mucous membranes, tachycardia, confusion, and hallucinations.
In more mechanistic detail, the toxic action of this genus occurs due to the anticholinergic action of alkaloids, which are acetylcholine antagonists at muscarinic receptors, inhibiting the action of this transmitter in autonomic effectors and smooth muscles, decreasing mucous secretions, and blocking the action of the myocardial vagus nerve, providing increased heart rate.
CNS Activity
Scopolamine and its derivatives have parasympatholytic, anticholinergic, antiemetic, and sedative actions; these substances are mainly used as pre-anesthetics. Due to their action, they become mydriatic and cycloplegic agents, with a mechanism similar to atropine. Individual alkaloids have distinct CNS profiles: scopolamine has an anticholinergic effect like atropine, but also has a strong depressant effect on the CNS, leading to apathy. Hyoscyamine is a form of atropine; it also has a spasmolysis effect and, like atropine, leads to dilation of the pupils (mydriatic). It has less effect on the heart but leads to stronger effects on the nervous system.
Pharmaceutical Derivatives
Compared to the parent hyoscyamine, scopolamine possesses a remarkably higher pharmaceutical activity and has less toxicity. Anisodamine, scopolamine, and related tropane alkaloids (e.g., atropine: (±)-hyoscyamine) are valuable pharmaceutical compounds with anticholinergic activity, produced as self-defence agents in plants of the Solanaceae family. These alkaloids, which show remarkable hallucinogenic and sedative effects, are used for the treatment of motion sickness, gastrointestinal spasms, and nausea. They are listed among the top compounds in the World Health Organization (WHO) essential drug catalogue, including atropine, ipratropium bromide, scopolamine butylbromide, and tiotropium bromide.
Anisodamine offers additional therapeutic applications such as the treatment of septic shock, circulatory disorders, gastric ulcers, respiratory diseases, gastrointestinal colic, organophosphorus poisoning, migraine, acute glomerular nephritis, eclampsia, and rheumatoid arthritis.
5. Scientific Evidence by Area of Use
Important note on evidence quality: The scientific investigations that have been carried out to date are scarce; the analgesic, cytotoxic, nematicidal, and antimicrobial activity has been studied. No controlled human clinical trials of Brugmansia as a botanical preparation have been identified in the peer-reviewed literature. The entirety of the evidence base for the plant itself (as distinct from its purified alkaloid derivatives) rests on in vitro experiments, animal studies, and observational/case-report data.
5.1 Analgesic and Antinociceptive Activity
Pharmacological studies demonstrated that the polar extract of leaves of B. suaveolens showed better nematicidal, antinociceptive, and wound healing activity as compared to non-polar extracts. A PMC review (2023) catalogued the therapeutic potential described in extracts and compounds in antitumor, anti-inflammatory, antioxidant, antimicrobial, antispasmodic, anticoagulant, and analgesic aspects, as well as effects on the central nervous system. These findings are derived from preclinical models and do not constitute human clinical evidence.
5.2 Antimicrobial Activity
A phytochemical and in vitro analysis of B. suaveolens for topical use (PubMed, 2022) found that biological assays showed the presence of different secondary metabolites, such as flavonoids and alkaloids, and demonstrated promising antimicrobial activity in gram-negative strains. Regarding safety, greater cytotoxicity was observed in macrophage cells. This is in vitro evidence only, with no translation to human clinical outcomes established.
5.3 Nematicidal Activity
A study published in the Asian Journal of Biology (2017) investigated leaf extracts of B. suaveolens against the root-knot nematode Meloidogyne incognita: the nematicidal activity of extracts of D. metel, D. innoxia, and B. suaveolens were studied against M. incognita. For nematicidal activity, the leaf extracts were used at different concentrations of 250 ppm, 500 ppm, 750 ppm, and 1000 ppm at different exposure times (24 hrs, 48 hrs, and 72 hrs). The in vitro nematicidal activity results confirmed that the extracts possessed nematicidal activity. Related research on tropane alkaloids confirmed that the tropane alkaloids hyoscyamine and scopolamine, in a series of in vitro experiments, were tested for nematicidal activity against the root-knot nematode Meloidogyne incognita. This evidence is entirely preclinical (in vitro / glasshouse experiments).
5.4 Antitumor / Anticancer Activity
A tropane alkaloid, hyoscyamine, is a major bioactive ingredient of the plant with reported anticancer activity. This claim is supported only by in vitro cell-line experiments. A 2025 PMC study used B. suaveolens extracts (among other solanaceous plants) against brine shrimps, cell lines (A549, HeLa, HEPG), and Caenorhabditis elegans as model systems. No human clinical trial data exist for the anticancer application of whole-plant Brugmansia extracts.
5.5 Wound Healing
Brugmansia suaveolens is pharmacologically proven for analgesic, antinociceptive, wound healing, nematicidal, and antimicrobial activities in preclinical contexts. Evidence is derived from animal models (e.g., studies by Schmidt et al., 2009, as cited in the ScienceDirect review) and in vitro assays. No human wound-healing trials have been published.
5.6 Pharmaceutical Alkaloid Applications (Purified Compounds)
While the whole plant has no established clinical therapeutic application, its purified alkaloids — when extracted, standardized, and pharmaceutically formulated — have well-documented clinical uses. Atropine and scopolamine are potent anticholinergic agents used in therapy in the form of sulfate salts for ophthalmic use and as gastrointestinal relaxants. These applications, however, involve pharmaceutical-grade isolated compounds with defined dosing, not the plant itself.
6. Body Systems and Health Areas Associated with Brugmansia
- Nervous System: Central anticholinergic effects including delirium, hallucinations, altered consciousness; historically exploited for ritual psychoactive purposes and studied for sedative/narcotic properties.
- Cardiovascular System: Tachycardia and vagal blockade via muscarinic receptor antagonism; atropine derivatives are used in clinical cardiology.
- Ocular System: Mydriasis (pupil dilation) and cycloplegia via muscarinic blockade; after ocular exposure to sap from B. suaveolens, seven patients developed unilateral mydriasis, at least three also had ipsilateral cycloplegia, and one developed transient tachycardia.
- Gastrointestinal System: Smooth muscle relaxation; used traditionally and pharmaceutically (as isolated scopolamine butylbromide) for GI spasm relief.
- Musculoskeletal System: Traditional topical application for arthritis, rheumatism, and pain; antinociceptive effects demonstrated in animal models.
- Integumentary System: Traditional application for wounds, dermatitis, abscesses, burns, and skin infections; antimicrobial activity demonstrated in vitro against gram-negative bacteria.
- Respiratory System: Popularly, its dried flowers and leaves are used to treat strong coughs and bronchitis by inhaling its vapor.
- Urinary System: Urinary retention is a known anticholinergic effect; a reported case showed urinary retention alongside mydriasis and sinus tachycardia following accidental leaf ingestion.
7. Dosage Forms and Reported Dosages
Because Brugmansia is not used as a standardized pharmaceutical preparation, there are no established therapeutic dosages. The following dosage-related data come entirely from toxicological reports and pharmacological studies, and are presented solely as documented in those sources.
- Flower alkaloid content (analytical): The toxic effect is mainly attributed to atropine and scopolamine; their averages in the flowers are 0.79 ± 0.03 mg/g and 0.72 ± 0.05 mg/g of dry plant, respectively.
- Nematicidal in vitro concentrations: Leaf extracts were tested at 250 ppm, 500 ppm, 750 ppm, and 1000 ppm in exposure times of 24, 48, and 72 hours.
- Animal analgesic study doses (as cited in PMC review): Doses of 100 and 300 mg/kg i.p. in mice have been referenced in analgesic assessments of plant extracts.
- Physostigmine antidote dosing (in poisoning management): As a specific antidote in severe poisonings, the cholinesterase inhibitor physostigmine can be used, which can cross the blood-brain barrier and antagonize central anticholinergic effects. The dosage is 0.02–0.06 mg/kg IV, slowly.
Because Brugmansia is a natural product, tropane alkaloid content can vary wildly by species, location, or weather, which can change the proportions and concentrations of scopolamine and atropine present in the leaves and flowers. This unpredictability is a fundamental reason no safe botanical dosage can be established.
8. Safety Considerations and Interactions
Overall Toxicity Profile
Brugmansia species are among the most toxic of ornamental plants. Poisoning by Brugmansia arborea constitutes an underestimated public health issue, especially in regions where the plant is widely accessible. This species contains high concentrations of tropane alkaloids, primarily responsible for inducing an anticholinergic toxidrome with potentially severe clinical manifestations. Documented cases of human poisoning with this plant are numerous and are characterized by an anticholinergic syndrome, flaccid paralysis, seizures, and death.
Anticholinergic Toxidrome
The classical presentation of Brugmansia poisoning is the anticholinergic toxidrome. A prospective case series reviewed all anticholinergic plant poisonings admitted to a major Australian toxicology unit between July 1990 and June 2000: thirty-three patients were presumed to have ingested Brugmansia spp. based on their description of the plant; median age was 18 years (interquartile range 16–20); 82% were males. Thirty-one ingested a brewed tea or parts of the plant (flower); thirty-one used it recreationally. Common clinical features were: mydriasis (100%), mean duration 29 hours (SD 13) and delirium (88%) with a mean duration of 18 hours (SD 12). Tachycardia only occurred in 11 of the 33 patients (33%). The investigators concluded that anticholinergic plant abuse is sporadic in nature; most cases were moderate in severity, requiring sedation only; severe toxicity was rare. Mydriasis and delirium were the commonest features. There were no deaths, seizures, or arrhythmias (excepting tachycardia). One patient had hypotension and two sustained accidental traumatic injuries.
A larger multi-center study in Taiwan involving 203 cases of Datura/Brugmansia suaveolens exposures reported: the most frequently observed clinical effect was mydriasis (53.2%), followed by confusion (40%), tachycardia (35.5%), dry mouth (35.5%), dizziness (34%), dry skin (32.5%), and delirium (31%). Seventy-three cases (36%) had severe effects; none of them died.
Severe and Rare Complications
Beyond the classic anticholinergic syndrome, severe complications have been reported in individual cases. Toxicity results in agitation, hallucinations, hyperthermia, tachycardia, rhabdomyolysis, renal failure, and death. At least one case report described fulminant hepatitis caused by "angel's trumpet" in addition to the neurological symptoms already described in the literature. Particularly concerning is the loss of control, which in delirious states can trigger horrifying trips and may even lead to self-mutilation.
The tropane alkaloids (atropine, scopolamine, hyoscyamine) contained in the plant have an anticholinergic effect and lead to characteristic poisoning symptoms such as mydriasis, dry mucous membranes, tachycardia, neurological disorders, and in severe cases, seizures and respiratory paralysis. In cases of severe intoxication, muscle relaxation, a drop in body temperature, and ultimately coma occur. Death occurs through central respiratory paralysis.
Ocular Exposure
After ocular exposure to sap from B. suaveolens, seven patients developed unilateral mydriasis, at least three also had ipsilateral cycloplegia, and one developed transient tachycardia. This demonstrates that significant systemic and local effects can occur via non-oral routes.
Drug Facilitation / Criminal Use
Scopolamine extracted or derived from Brugmansia-related plants has been documented in drug-facilitated crimes. In one documented case, clinical symptoms of decreased consciousness, mydriasis, confusion, hallucinations, and urine retention indicated anticholinergic syndrome; an extended toxicological analysis of urine revealed the presence of the alkaloid scopolamine. The analytical results along with the victim's account indicated that she had been subjected to a drug-facilitated crime, further demonstrating that in suspected cases of involuntary drug exposure, testing should cover a wide panel of relevant drugs.
Epidemiological Patterns by Region
Accidental poisoning with Datura and Brugmansia suaveolens is by far the most common incidence in Asian countries with wrongful use of traditional medicines. Whereas in Central and North America, Brugmansia suaveolens toxicity is mostly due to abuse ingestion, especially among the younger population. The Taiwan multi-center study found that a total of 203 cases were eligible for analysis; using Datura/Brugmansia for a medicinal purpose by patients without consulting Chinese medicine practitioners was the most common reason for poisoning (81.2%), whereas only 2% were poisoned after medicinal use associated with prescription from Chinese medicine practitioners. None of the 203 patients had used the plant for recreational purposes.
Antidotal Treatment
Physostigmine is recommended as antidotal therapy in cases of delirium secondary to anticholinergic toxicity, including belladonna alkaloid poisoning. Forty patients (19.7%) in the Taiwan study received physostigmine therapy, and patients receiving physostigmine had an earlier resolution of central nervous system toxicity than those who did not. Consumption of parts other than flowers and misidentification of the plants predicted the severity of poisoning. Patients who received physostigmine appeared to have earlier improvement in CNS effects. No adverse events were reported from physostigmine administration.
Drug Interactions
Because the primary active alkaloids are muscarinic receptor antagonists, combination with other anticholinergic substances is expected to produce additive toxicity. At least one documented case involved a patient who had taken both diphenhydramine (an antihistamine with anticholinergic properties) and angel's trumpet. Concurrent use of other antimuscarinic medications (e.g., tricyclic antidepressants, antihistamines, antispasmodics, antiparkinsonian drugs) would be expected to markedly worsen anticholinergic toxicity based on the shared pharmacological mechanism.
Variability of Alkaloid Content
The concentration of the different compounds varies according to the biotic and abiotic factors to which the plant is exposed. This chemical variability means that even experienced users cannot reliably predict the potency of a given plant preparation, which contributes to the risk of severe poisoning with doses that might otherwise have appeared moderate.
References
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