Introduction 

Atropa Belladonna, is a plant you want to avoid due to its poisonous and even deadly properties. The name Atropa Belladonna is derived from both Greek mythology where ‘Atropa’ refers to a Greek goddess of fate who determines birth, life and death and Belladonna comes from the Italian language translating as ‘beautiful woman’. The context behind this name refers to the primeval cosmetic use of Atropa Belladonna to dilate pupils of women to enhance their beauty and conversely a reference to the toxic qualities of the plant that can result in death. The plant may also be referred to as deadly nightshade or even ‘Devil’s cherries’.^1,2

Historically, the plant has been used for a very long time and even today has application in medicines for motion sickness, abdominal issues, as an anesthetic and in droplet form can be used for pupil dilation. But this does not take away from the dangers of the plant and so this article aims to provide an overview of the plant so that the general public have reduced risks of poisoning.³

Where Is Belladonna Found?

Originally Atropa Belladonna was only found in mild temperature climates within Europe and Asia but now it can be found in many areas of the world due to its medicinal purposes. Naturally, it can be located in quarries, waste land or even on woodland paths. In the UK, it grows on calcareous soil which contains a large amount of a compound called calcium carbonate.⁴ The plant itself can be described as a branching bushy herb that can be up to five feet tall. It has purple and green flowers and small individual black berries which are sweet in taste. The berries typically ripen in late August or September but despite their palatable taste they are not edible and honey produced by bees from these berries is also toxic to humans.⁵

How Belladonna Poisoning Happens

There are a few way in which a individual can experience Belladonna poisoning: 

• Ingestion: This is the most common route and involves ingesting any part of the plant (leaves, flowers, roots or fruits). Typically children accidentally ingest the berries as they can resemble non-poisonous blackcurrants or blueberries. However there are occasions when the plant is ingested for suicide attempts²
• Skin contact: Handling this plant can cause toxins to be absorbed through the skin although it may not be enough to be poisonous it may cause contact dermatitis¹
• Inhalation: In ancient times, due to hallucinogenic effects the plant was inhaled and this can be poisonous if done extensively⁶
• Through an intermediate source: Consuming cattle who have been fed Atropa Belladonna or eating honey from the fruits of the plant⁷

The Poisonous Nature of Belladonna

The toxic part of the Atropa Belladonna are substances called tropane alkaloids specifically atropine, hyoscyamine, and scopolamine which are found in all parts of the plant. The roots are the most toxic with an alkaloid content of 1.3%, the leaves have 1.2% and the ripe berries have 0.7%. They reach the highest toxicity content during the budding and flowering season.⁸ The mechanism of action of the tropane alkaloids is causing anticholinergic toxicity by competitively blocking the binding of an important neurotransmitter called acetylcholine to the parasympathetic postganglionic muscarinic receptors and those of the central nervous system. Blocking these receptors can cause central and peripheral effects and symptoms including involuntary responses of the parasympathetic nervous system including heart rate, breathing and sweating.⁹

The plant’s toxicity is also dose dependent and the effect will also vary from individual to individual, as in some cases where individuals such as children are more sensitive as little as 10 mgm can cause intoxication.  The average lethal dose is estimated to be between 90 and 130 mgm.⁷

It can also cause additional complications in people with disorders affecting the cardiovascular system, the gastrointestinal and the nervous system, as well as pregnant women. 

It is not only considered toxic to humans, many domestic animals like dogs and cats will also experience intoxication symptoms but on the other hand cattle and rabbits are unharmed when they graze upon this plant.⁸

Signs and Symptoms of Belladonna Poisoning

The symptoms of Belladonna poisoning can be separated into either central or peripheral anti- cholinergic effects. 

Central Nervous system manifestations: 

As the alkaloids in the plant block the muscarinic (parasympathetic) receptors for acetylcholine, this reduces their normal function in the brain for memory, orientation and learning. This can lead to:

• Hallucinations 
• Disorientation 
• Confusion 
• Reduced memory 
• Ataxia 
• Psychosis 
• Agitation 
• Delirium 
• Seizures 
• Coma 
• Respiratory and cardiac failure^3,9

Peripheral Nervous system manifestations: 

The alkaloid atropine has the strongest effect here by blocking the parasympathetic postganglionic muscarinic receptors. It can cause: 

• Tachycardia 
• Hypertension
• Vomiting 
• Constipation 
• Dry mouth 
• Dilated pupils 
• Flushed skin 
• Urinary retention 
• Diminished bowel sounds 
• Inhibition of gastric acid secretion 

The severity of symptoms varies depending on dose, concentration and source of the plant. Some species of this plant are considered ‘hybrid’ which means they don’t produce all of the toxic effects.^9,10

Diagnosis of Belladonna Poisoning

Identifying Atropa Belladonna poisoning is largely based on the clinical presentation of the patient. 

• Initially a full physical examination should be carried out, making sure to check blood pressure, pulse rate, respiratory rate
• A neurological examination should follow and a Glasgow coma scale should be determined
• Finding out about the medical, social and family history is also important so that the plant can be rapidly identified
• Blood tests can then be used to determine the presence of the tropane alkaloids in the blood⁶

You must also considered excluding differential diagnosis which can present with similar symptoms such as:

• Acute psychosis 
• Traumatic brain injuries 
• Ingestion of other drugs with anticholinergic effects e.g. antihistamines 
• Ingestion of other harmful plants like Jimson weed²

Treatment for Belladonna Poisoning

The initial antidote for Belladonna Poisoning is Physostigmine which is especially useful in life threatening cases. It works by reversibly inhibiting anticholinesterase in order to increase the levels of acetylcholine and to reduce the neurological symptoms as it is able to cross the blood brain barrier. It is also good for more severe symptoms like ​​tachycardia, respiratory arrest and coma. However, the drug should be used with caution as it can have side effects like those involved with the cardiac system and nervous system. If Physostigmine is unavailable then pilocarpine which is a cholinomimetic can be used. 

Other urgent treatment is the use of activated charcoal if the Belladonna has been ingested, this substance can absorb the toxin from the stomach effectively. This is often used with a gastric lavage through a nasogastric tube. 

Other treatment is through managing symptoms like agitation and delirium and so drugs like Benzodiazepines can be used to sedate the patient.²

Typically within 72 to 96 hours, the alkaloids will be eliminated through the urine and the patient will be able to recover but monitoring and consistent observation is very important during this period. The only symptoms that may persist after this may be difficulties with eyesight and urination but they tend to resolve after a few days.¹¹

Preventing Belladonna Poisoning

To prevent cases of Atropa Belladonna intoxication you should: 

• Educate children on poisonous plants and their appearance 
• Identify and remove any belladonna plants from your own garden, making sure to use protective equipment when handling it
• Make sure to remove all roots of the plant as this is not only toxic but also has the ability to regrow again
• Dispose plant and disinfect tools
• Make sure healthcare professionals are aware of this poisoning and the antidote⁵

Summary 

Atropa Belladonna is a plant which is known for its poisonous effects when ingested, inhaled or through topical exposure. It can be found in many areas of the world, usually located in quarries, waste land or even on woodland paths. The plant’s toxic components are the tropane alkaloids specifically atropine, hyoscyamine, and scopolamine which are found in all parts of the plant. 

They act by competitively blocking the binding of acetylcholine to the peripheral and central parasympathetic postganglionic muscarinic receptors. Blocking these receptors can cause central and peripheral symptoms including involuntary responses of the parasympathetic nervous system including heart rate, breathing and sweating. 

Diagnosis is based on these symptoms and through blood tests. Treatment involves the use of an antidote, activated charcoal, benzodiazepines and overall supportive observation. It is important to be aware of the dangers of this plant to prevent accidental poisoning in both children and adults.^2,11