Angel’s Trumpet (Brugmansia Suaveolens)
Angel’s Trumpet (Brugmansia suaveolens) belongs to the nightshade family (Solanaceae) and is classified as highly toxic (+++) due to its high concentration of tropane alkaloids. These trumpet-shaped flowers, often cultivated as ornamental plants in gardens, pose a significant danger to our pets. The main toxic substances in Angel’s Trumpet are atropine, scopolamine, and hyoscyamine, which belong to the group of tropane alkaloids. These toxins are present in all parts of the plant, with the highest concentrations found in seeds and flowers. Even the ingestion of small amounts can lead to severe poisoning symptoms in dogs and cats.
The most important facts at a glance
Angel’s Trumpet (Brugmansia suaveolens) is among the highly toxic plants and poses a significant danger to dogs and cats. The contained tropane alkaloids (atropine, scopolamine, hyoscyamine) have anticholinergic effects and lead to characteristic poisoning symptoms such as mydriasis, dry mucous membranes, tachycardia, neurological disturbances, and in severe cases, convulsions and respiratory paralysis.
Diagnosis is based on history, clinical picture, and supportive laboratory tests. Therapy includes decontamination measures, administration of activated charcoal, specific antidote therapy with physostigmine for severe poisonings, and symptomatic measures to stabilize vital functions. With early and adequate treatment, the prognosis is favorable in most cases, while severe poisonings can be life-threatening.
Preventive measures, such as removing toxic plants from the animals’ environment, are crucial to prevent poisonings. Pet owners should be educated about the dangers of Angel’s Trumpet and other toxic plants and seek immediate veterinary help in case of poisoning.
Causes, development and progression
The Angel’s Trumpet shares its toxic properties with other nightshade plants such as thorn apple (Datura), nightshade (Solanum), belladonna (Atropa), henbane (Scopolia), mandrake (Mandragora), and henbane (Hyoscamus). In all these plants, the mechanism of poisoning is similar and is based on the anticholinergic effect of the tropane alkaloids they contain. The heart and nervous system are particularly affected.
It initially leads to states of excitement and cramps, later to movement disorders and paralysis, as well as shortness of breath. Paralysis of the muscles of the gastrointestinal tract and urinary tract leads to constipation and difficulty urinating. In human medicine, the ingestion of even a few flowers or leaves is considered toxic.
Angel’s Trumpet poisoning usually occurs through oral ingestion of plant parts. Dogs and cats may chew or eat the plants out of curiosity or boredom. After oral ingestion, the tropane alkaloids are rapidly and completely absorbed from the gastrointestinal tract and distributed throughout the body tissue. Excretion later occurs partly unchanged via the kidneys.
The risk of poisoning is particularly high during the flowering season of the Angel’s Trumpet from June to October, but can exist all year round if the plant is kept as a houseplant. While cats are less likely to be affected due to their more selective eating habits, young, inexperienced dogs in particular tend to explore and eat plant parts. Animals with certain pre-existing conditions, especially of the heart or nervous system, also have an increased risk of serious complications from Angel’s Trumpet poisoning.
The mechanism of action of tropane alkaloids is based on their ability to inhibit the effect of the neurotransmitter acetylcholine. Atropine blocks the muscarinic acetylcholine receptors, thus inhibiting the parasympathetic nervous system. Scopolamine has a similar anticholinergic effect, but also has a strong sedative effect on the central nervous system and can trigger seizures. Hyoscyamine, a form of atropine, also has a spasmolytic effect and leads to dilation of the pupils, but has stronger effects on the nervous system than atropine.
Mechanism of action
Atropine inhibits the effect of the neurotransmitter for nerve excitation between the nerve cell and other cells.
The name of the neurotransmitter is acetylcholine. The effect is called anticholinergic.
The anticholinergic effect is particularly noticeable in digestive processes (saliva secretion, tone in the gastrointestinal tract and gallbladder), on the heart and on the CNS.
Scopolamine
Scopolamine has an anticholinergic effect like atropine. However, it has a strong sedative effect on the CNS and leads to apathy. Cramps are sometimes triggered.
Hyoscyamine
Hyoscyamine is a form of atropine. It also has a spasmolytic 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.
When higher doses are absorbed, it initially has an exciting effect on the CNS, leading to cramps.
In severe intoxication, muscle relaxation, a drop in body temperature and ultimately coma occur.
Death occurs due to central respiratory paralysis.
In humans, the LD is 50–100 mg.
The Angel’s Trumpet (genus Brugmansia) belongs to the nightshade family (Solanaceae) and contains highly potent tropane alkaloids. These alkaloids have a toxic effect on the central and peripheral nervous system and lead to severe poisoning in dogs and cats even in small quantities.
The toxic substances in the plant are:
- Atropine
- Scopolamine
- Hyoscyamine
These substances are found in all parts of the plant, but are particularly concentrated in the seeds and flowers. Just a few grams of the plant can cause significant intoxication.
Pharmacological mechanism of action
The tropane alkaloids mentioned are competitive antagonists at muscarinic acetylcholine receptors (mAChR) in the parasympathetic nervous system. This means:
- They block the effect of acetylcholine, one of the most important messenger substances of the autonomic nervous system.
- This leads to an inhibition of parasympathetic reactions and thus to a predominance of sympathetic effects in the body.
Specifically, this means:
- Dilation of the pupils (mydriasis)
- Increased heart rate (tachycardia)
- Inhibition of saliva and gastric juice secretion → dry mucous membranes
- Reduced intestinal motility → constipation, bloating
- Urinary retention due to detrusor relaxation
- Stimulation of the central nervous system → restlessness, hallucinations, seizures
Scopolamine also has a strong central sedative effect and can lead to disorientation, impaired consciousness and coma. Atropine primarily has peripheral effects, but also has CNS effects in toxic doses.
Specific effect in dogs
- Dogs often show a mixture of central nervous system stimulation and vegetative disinhibition:
- Restlessness, nervousness, hallucinatory behavior
- Dry mucous membranes, panting, oversized pupils
- Rapid heartbeat, circulatory instability
- In severe cases: seizures, coma, respiratory paralysis
Specific effect in cats
- Cats are particularly sensitive to tropane alkaloids, both peripherally and centrally:
- Sudden change in behavior, states of excitement or apathy
- Hyperthermia due to lack of sweat secretion and central nervous system decoupling of temperature regulation
- Tremors, coordination disorders, muscle twitching
- Seizures, collapse, respiratory depression
Cats also show signs of central nervous system overstimulation more quickly with visual hallucinations (so-called “chasing flying insects”) and massive disorientation.
Summary of the mechanism of action
| System | Toxic effect of tropane alkaloids |
| Central nervous system | Excitation (atropine), sedation (scopolamine), hallucinations, seizures |
| Eyes | Pupil dilation (mydriasis), sensitivity to light |
| Cardiovascular system | Tachycardia, increase or decrease in blood pressure, arrhythmias |
| Gastrointestinal tract | Dry mouth, reduced gastrointestinal motility, constipation |
| Urogenital system | Urinary retention due to detrusor inhibition |
| Temperature regulation | Hyperthermia due to central and peripheral inhibition of cholinergic pathways |
Symptoms of intoxication
Reduced saliva production
Intestinal peristalsis inhibited (spasmolysis, intestinal inertia)
Urinary retention
Gallbladder, tone reduced
Dilation of the pupils
Tachycardia (increased heart rate)
Excitation
Disorientation
Apathy
Seizures
Respiratory paralysis
The clinical signs of Angel’s Trumpet poisoning can be very diverse in dogs and cats and usually occur within 30 to 60 minutes after ingestion. The symptoms reflect the anticholinergic effect of the tropane alkaloids and affect several organ systems:
In the digestive tract, there is reduced saliva production with dry mucous membranes, inhibited intestinal peristalsis (spasmolysis) and resulting constipation. The reduced motility of the gastrointestinal tract can lead to nausea and vomiting, although the latter usually only occurs at the beginning of the poisoning.
In the urogenital tract, the poisoning manifests itself as urinary retention due to reduced bladder contraction. The tone of the gallbladder is also reduced, which can lead to disorders in bile metabolism.
The effects on the nervous system and eyes are particularly characteristic. The affected animals show a clear mydriasis (pupil dilation), which has a symmetrical effect on both eyes and does not react to light. Paradoxical reactions can occur in the central nervous system: Initially, the animals often show states of excitement, restlessness, disorientation and coordination disorders, later apathy, seizures and finally unconsciousness can follow.
Cardiovascular symptoms include tachycardia (increased heart rate) and arrhythmias. The mucous membranes may appear pale or cyanotic due to circulatory changes. In severe cases, hyperthermia (increased body temperature) can occur because sweat production is inhibited and heat regulation is disturbed.
Respiratory problems manifest as shallow, rapid breathing, which can lead to central respiratory paralysis as the poisoning progresses, which is ultimately the cause of death.
Diagnosis
The diagnosis of Angel’s Trumpet poisoning is initially based on the patient’s history and the clinical picture. If the pet owner has observed their animal eating parts of an Angel’s Trumpet, or if typical plant residues are found in the vomit, this is an important diagnostic indicator. The characteristic symptom profile, including mydriasis, dry mucous membranes, tachycardia, and neurological abnormalities, supports the presumptive diagnosis.
Laboratory tests can help assess the severity of the poisoning and identify complications. A complete blood count (CBC) and blood chemistry should be performed to check liver and kidney function, as these organs are involved in the metabolism and excretion of toxins. Electrolyte disturbances, particularly changes in potassium and sodium, can occur and should be monitored.
An ECG is indicated if cardiac arrhythmias are suspected and can show tachycardia, extrasystoles, or other arrhythmias. In severe cases, a blood gas analysis may be necessary to assess the acid-base balance and oxygenation.
Direct detection of tropane alkaloids in blood or urine is rarely available in routine diagnostics but can be performed in specialized laboratories. In practice, however, this detection is usually not necessary, as treatment is symptom-oriented.
Differentially, other anticholinergic poisonings (e.g., due to certain medications like antihistamines or tricyclic antidepressants), as well as neurological diseases such as epilepsy or meningoencephalitis, must be considered.
Therapeutic principles
The cholinesterase inhibitor physostigmine can be used as an antidote.
By inhibiting the breakdown of acetylcholine, physostigmine counteracts the effect of atropine, so that more acetylcholine is available again and for a longer period of time.
The primary decontamination should be carried out as quickly as possible and include all sensible measures consistently.
These are inducing vomiting, provided the animal is responsive and there are no seizures, as well as gastric lavage.
Afterwards, activated charcoal should be given repeatedly. Increasing intestinal passage after the administration of activated charcoal accelerates elimination.
To secondary poison elimination, that is, the elimination of already absorbed poisons, serves an increase in urine formation by volume substitution and the use of special drugs (forced diuresis).
The symptomatic therapy serves to stabilize vital functions and combat distressing symptoms such as seizures, persistent vomiting or pain.
Treatment of Angel’s Trumpet poisoning requires a rapid and comprehensive therapeutic approach. The primary measure is decontamination to prevent further absorption of the poison. If ingestion occurred less than 1–2 hours ago and the animal is conscious and not showing seizures, inducing vomiting by administering apomorphine (dog) or xylazine (cat) may be useful. Inducing vomiting is contraindicated in animals with impaired consciousness or seizures.
Gastric lavage under anesthesia can be considered if vomiting was unsuccessful or is contraindicated. Following these measures, activated charcoal should be administered several times (1–4 g/kg body weight every 4–6 hours) to reduce the absorption of toxins still in the intestine. The administration of laxatives such as sodium sulfate accelerates intestinal passage and thus the excretion of toxins.
The cholinesterase inhibitor physostigmine, which can cross the blood-brain barrier and thus also antagonize central anticholinergic effects, can be used as a specific antidote in severe poisoning. The dosage is 0.02-0.06 mg/kg i.v. slowly. The effect begins within minutes, but only lasts about 1–2 hours, so repeated doses may be necessary. Physostigmine should be used with caution as it can have toxic effects itself, especially in overdose or in animals with heart disease.
Symptomatic therapy includes stabilization of vital functions. For seizures, benzodiazepines such as diazepam (0.5-2 mg/kg i.v.) or midazolam are used. Fluid therapy is important to promote the excretion of toxins via the kidneys (forced diuresis) and to stabilize the circulation. Cooling measures are indicated for hyperthermia.
Monitoring of heart function using continuous ECG is recommended in severe poisoning. Antiarrhythmics such as lidocaine or beta-blockers can be used for arrhythmias. Oxygen therapy should be performed for shortness of breath or cyanosis. In severe cases, mechanical ventilation may be required.
Prognosis & follow-up care
The prognosis of Angel’s Trumpet poisoning depends largely on the amount of toxin ingested, the time until the start of therapy and the intensity of the therapeutic measures. With early and adequate treatment, the prognosis is favorable in most cases. Animals that survive within the first 24–48 hours after ingestion have a good chance of complete recovery without long-term damage.
In severe poisoning with pronounced neurological symptoms, especially if seizures or unconsciousness have occurred, the prognosis should be more cautious. Complications such as aspiration pneumonia from vomiting, kidney failure from dehydration or cardiac arrhythmias can negatively affect the course of the disease.
Follow-up care after surviving Angel’s Trumpet poisoning includes regular check-ups to detect possible organ damage early. The kidney and liver function should be monitored primarily by blood tests. An ECG can be useful to rule out latent cardiac arrhythmias.
Pet owners should be informed that Angel’s Trumpet and other nightshade plants should be removed from the animals’ environment to avoid re-poisoning. Alternatives for garden design are non-toxic ornamental plants such as hibiscus, roses or certain types of hydrangeas.
Research outlook
Research in the field of plant poisoning in pets is continuously evolving. Current studies focus on improving diagnostic methods for the rapid and reliable detection of tropane alkaloids in biological samples. New analytical methods such as high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS) enable more precise quantification of toxins and could also be used in routine veterinary diagnostics in the future.
Another research focus is on the development of more specific antidotes with fewer side effects than the currently used cholinesterase inhibitors. Modified physostigmine derivatives or novel anticholinergic antagonists could enable safer and more effective treatment in the future.
Research into individual factors that influence sensitivity to tropane alkaloids is also gaining importance. Genetic differences in the metabolism of these substances could explain why some animals react more sensitively than others. These findings could lead to personalized treatment protocols tailored to the specific needs of the individual animal.
Finally, research is increasingly dedicated to the development of training methods and deterrents to prevent pets from eating toxic plants. Behavior modification techniques and natural repellents could play an important role in the prevention of plant poisonings in the future.
Frequently asked questions (FAQs)
- How quickly do the symptoms of Angel’s Trumpet poisoning appear in my pet?
The first symptoms usually appear within 30–60 minutes after ingestion of the plant and can last up to 24–48 hours. - What amounts of Angel’s Trumpet are toxic to my pet?
Even small amounts can be toxic. In dogs, a few leaves or a flower may be enough to cause poisoning symptoms. Cats are even more sensitive due to their lower body weight. - Are certain pets more susceptible to Angel’s Trumpet poisoning?
Young, curious dogs are particularly at risk. Cats are less likely to be affected due to their more selective eating habits, but can also be poisoned. - Can my pet die from Angel’s Trumpet poisoning?
Yes, untreated severe poisoning can lead to death from respiratory paralysis. However, with timely veterinary treatment, the prognosis is usually good. - How can I protect my pet from Angel’s Trumpet poisoning?
The safest method is not to plant Angel’s Trumpets and other toxic plants in gardens that pets have access to. Alternatively, barriers can be erected or the animals can be supervised. - Are there differences in the toxicity of different Angel’s Trumpet species?
Yes, the content of tropane alkaloids can vary between different species and even between individual plants. However, all species of the genus Brugmansia are to be classified as highly toxic. - Can poisoning symptoms also occur with a delay?
The symptoms usually appear quickly, but some neurological symptoms may appear with a delay, especially if only small amounts were ingested initially. - How long does it take to recover from Angel’s Trumpet poisoning?
In mild to moderate poisoning, complete recovery can take 2–3 days. In severe poisoning with organ damage, recovery can take several weeks. - Are there long-term consequences after surviving poisoning?
With adequate treatment, long-term consequences are rare. However, in severe cases, neurological damage or organ damage, mainly to the kidneys and liver, can remain. - Is it possible for my pet to develop a tolerance to the toxins in Angel’s Trumpet?
No, animals do not develop a tolerance to tropane alkaloids. Each re-exposure can lead to poisoning, which may be more severe than the previous one.
Literature
Burrows, G. E. and Tyrl, R. J., 2013. Toxic Plants of North America. 2nd Edition. Hoboken: John Wiley & Sons.
- Gwaltney-Brant, S. M., 2021. Plant Poisonings in Small Animals. Veterinary Clinics of North America: Small Animal Practice, 51(6), pages 1195–1212. Available at: https://doi.org/10.1016/j.cvsm.2021.06.005 [Accessed July 6, 2025].
- Krenzelok, E. P. and Mrvos, R., 2021. Toxic plant ingestions in companion animals: A comprehensive review of prevention and management strategies. Journal of Veterinary Emergency and Critical Care, 31(2), pages 141–152. Available at: https://doi.org/10.1111/vec.13045 [Accessed July 6, 2025].
- Löwe, G. and Löwe, O., 2021. Poisoning in Dogs and Cats – A Veterinary Guide. 2nd edition. Kreuztal: Kynos-Verlag. 208 pages.
- Osweiler, G. D., 2011. Toxicology of Domestic Animals. Boca Raton: CRC Press.
- Peterson, M. E. and Talcott, P. A., 2022. Small Animal Toxicology. 4th Edition. St. Louis: Elsevier Health Sciences. ISBN 978-0323546331.
- Plumlee, K. H., 2019. Clinical Veterinary Toxicology. 3rd Edition. St. Louis: Mosby Elsevier. ISBN 978-0323595391.