Belladonna or Deadly Nightshade Dangers and Atropine Uses

A deadly nightshade flower and an unripe berry
A deadly nightshade flower and an unripe berry | Source

A Deadly Plant and a Useful Chemical

The deadly nightshade plant, also known as belladonna, is so poisonous that eating as few as two berries can kill a child. The plant contains atropine and other dangerous alkaloid chemicals, including scopolamine and hyoscyamine. Despite its toxicity, when used in small quantities atropine has important medical applications.

Deadly nightshade is native to Europe, North Africa and Western Asia, but the plant grows in North America, too. Its scientific name is Atropa belladonna. All parts of the plant are poisonous.

The flowers of the deadly nightshade plant are bell-shaped and are purple and green in color. The large, oval leaves have pointed tips. Unripe berries are green. As they ripen, the berries become black, shiny and beautiful. The deadly nightshade is sometimes called black cherry or devil’s cherries, because although the berries look appetizing they are actually very toxic.

An illustration showing the parts of the deadly nightshade plant
An illustration showing the parts of the deadly nightshade plant | Source

Effects of Deadly Nightshade Poisoning

Not only is eating any part of the deadly nightshade dangerous, but simply touching the plant can be harmful if the skin has cuts. There are many possible symptoms of poisoning, including:

  • rapid heartbeat
  • dry mouth
  • slurred speech
  • light sensitivity
  • blurred vision
  • inability to urinate
  • loss of balance
  • flushed skin
  • a rash
  • memory loss
  • seizures
  • confusion
  • hallucinations

Severe poisoning can cause paralysis, a coma and respiratory failure. Deadly nightshade is definitely a plant that should be admired from a distance.

Devil's Cherries or Deadly Nightshade Berries

A synapse: the region where a neurotransmitter such as acetylcholine travels across the gap between one nerve cell and another or between a nerve cell and a muscle cell
A synapse: the region where a neurotransmitter such as acetylcholine travels across the gap between one nerve cell and another or between a nerve cell and a muscle cell | Source

How Does Atropine in Deadly Nightshade Affect the Body?

Our nervous system produces acetylcholine. This chemical is a type of excitatory neurotransmitter – a substance released from the end of a stimulated nerve cell in order to stimulate the next nerve cell and transmit a nerve impulse. The acetylcholine must bind to a receptor on the second nerve cell in order to do its job. One type of acetylcholine receptor is known as a muscarinic receptor.

Atropine binds to muscarinic receptors, stopping acetylcholine from joining to the receptors. Atropine can therefore stop the transmission of nerve impulses. Muscarinic receptors are also present in smooth muscle, so atropine can inhibit the activity of muscles as well as nerve cells. Smooth muscle is found in our organs and blood vessels.

Berries and leaves of the deadly nightshade plant
Berries and leaves of the deadly nightshade plant | Source

Effect on the Parasympathetic Nervous System

Our autonomic nervous system - the part of the nervous system that we can't control voluntarily - consists of two divisions.

  • The sympathetic division of the nervous system prepares our bodies for emergencies. It’s often said to stimulate the “flight or fight” response. It causes the heart to beat faster, the breathing rate to increase and the pupils to dilate. It also inhibits digestion.
  • The parasympathetic division of the nervous system produces the opposite effects to the sympathetic system and is sometimes called the “rest and digest” system. The parasympathetic system relaxes the body, slows the heartbeat and breathing rate, constricts the pupils and stimulates digestion.

Atropine interferes with the action of the parasympathetic nervous system because the nerve cells of this system release acetylcholine. Atropine blocks the muscarinic receptors of the system, preventing acetylcholine from transmitting nerve impulses. Without the action of parasympathetic nerves, the body is unable to counteract sympathetic stimulation and the balance between sympathetic and parasympathetic stimulation is destroyed.

Atropine speeds up the heartbeat.
Atropine speeds up the heartbeat. | Source

Atropine and the Heart

Eating atropine inside a part of the deadly nightshade plant is very dangerous, but small amounts of atropine used in medications can be helpful. Atropine used as a medicine must be prescribed by a doctor.

Atropine injections are given to speed up a very slow heartbeat. The atropine blocks the action of the vagus nerve. This nerve is part of the parasympathetic nervous system and slows down the heartbeat. When the action of the vagus nerve is inhibited by atropine, the heart will beat faster.

Atropine dilates the pupils of the eyes.
Atropine dilates the pupils of the eyes. | Source

Atropine and the Eyes

Atropine is also used in eye drops to make the pupils dilate so that a doctor can examine the inside of the eyes properly. The pupils stay dilated for several days. It’s been reported that in earlier times some Italian women would use belladonna to dilate their pupils, making them look more attractive. The name “belladonna” means “beautiful lady” and supposedly comes from this use. The women’s vision would also have become blurred, since atropine inhibits accommodation – the process in which the lens changes shape to focus on objects at different distances from the eye.

The deadly nightshade
The deadly nightshade | Source

Digestive Tract Effects

Food is passed along the digestive tract by wave-like contractions in the intestinal wall called peristalsis. Acetylcholine binds to muscarinic receptors in the muscles of the intestinal wall, triggering the muscles to contract. Atropine binds to these receptors and blocks acetylcholine. This calms the stomach and intestinal muscles and slows the frequency and strength of muscle contractions. Atropine has therefore been used to treat conditions such as irritable bowel syndrome.

Effects on the Urinary Bladder and Urination

The parasympathetic nervous system triggers urination by two methods. It stimulates the muscle in the urinary bladder wall to contract, which causes urine to be pushed out of the bladder. In addition, it relaxes the sphincter muscle that surrounds the passageway which transports urine out of the bladder. When the sphincter muscle contracts, the passageway is closed and the bladder is able to fill with urine. The parasympathetic nervous system counteracts this process, allowing urine to be released.

Since atropine inhibits the activity of the parasympathetic nervous system it reduces urination. Atropine also inhibits spasms of the urinary bladder. These abilities help some urinary system problems.

Amanita muscaria, which contains muscarine. Muscarinic receptors were given their name because they are stimulated by muscarine.
Amanita muscaria, which contains muscarine. Muscarinic receptors were given their name because they are stimulated by muscarine. | Source

Other Medical Uses of Atropine

Body Secretions

Atropine decreases the production of body secretions, including saliva, mucus and sweat. It's been used in cough syrups to help clear the airways.

Sedation

Atropine is sometimes used as a sedative. It’s known that acetylcholine is used as a neurotransmitter in the brain as well as in the parasympathetic nervous system, which is why atropine can affect brain functions when it interferes with the action of acetylcholine.

Inhibiting Chemical Weapons

Most chemical weapons that act on nerves belong to a group of chemicals known as organophosphates. These chemicals prevent acetylcholine from being broken down once it has done its job, so the acetylcholine continues to stimulate nerves. Atropine is used as an antidote to these nerve agents, since it blocks acetylcholine receptors, preventing the acetylcholine from reaching the nerves. Military personnel may carry an atropine auto-injector to protect themselves from chemical weapons.

Bittersweet Nightshade

The Bittersweet Nightshade Plant

The bittersweet nightshade, Solanum dulcamara, is sometimes known as deadly nightshade. It's poisonous and can sometimes be deadly, but it's not as toxic as the true deadly nightshade. An alternate name for the plant is woody nightshade. It's a perennial vine which is native to Europe and Asia but is widespread in North America.

The attractive flowers of the bittersweet nightshade have blue or purple petals. The petals are curved backwards, revealing a yellow or orange center. The berries are green when unripe and bright red when ripe. The leaf has one large lobe and a pair of small lobes at the base.

Beautiful bittersweet nightshade flowers
Beautiful bittersweet nightshade flowers | Source

Toxins in Bittersweet Nightshade

All parts of the bittersweet nightshade are poisonous. One of the toxic chemicals in the plant is solanine, which is also found in green potatoes. The plant also contains dulcamarine, which has quite similar effects to atropine.

In a way, the bittersweet nightshade is more dangerous than deadly nightshade, even though it's less poisonous. It's more common than deadly nightshade, so children, pets and livestock are more likely to encounter it. Eating bittersweet nightshade can potentially kill children and animals, but human deaths are quite rare. A doctor or veterinarian must always be consulted if a person or animal has eaten the plant, however.

Bittersweet nightshade berries
Bittersweet nightshade berries | Source

Plants to Admire and Avoid

The deadly and bittersweet nightshades are attractive and interesting plants, but they need to be treated with a great deal of respect. I often see the bittersweet nightshade during my walks and always admire its pretty flowers and berries. I enjoy observing and photographing the plant, but I keep its potential dangers in mind.

Toxic plants can have benefits, such as the production of atropine and other medically useful chemicals. It's very important that children (and adults) avoid touching the plants or eating any part of them, however. Younger children should be monitored when they are out of doors. Children that are old enough to leave the home on their own should be taught how to identify poisonous plants that they may encounter. Nature is often beautiful and offers us wonderful benefits, but it can sometimes be dangerous.

References and Further Reading

Belladonna Information from the NIH (National Institutes of Health)

Atropine Ophthalmic from the NIH

The Bittersweet Nightshade - A Weed of Concern from the government of King County

© 2010 Linda Crampton

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Comments 16 comments

shakes 3 years ago

i want to eat it


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Deadly nightshade is very poisonous and may kill people. Eating any part of the plant is extremely dangerous. It should never be eaten.


LydiaH 3 years ago

It's rather fascinating, if I may say so.

One question - once ingested, how long does it take for death to occur? Also, is there an antidote to the poison?


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Hi, LydiaH. The survival time varies considerably. It depends on several factors, such as the amount and part of the plant that's ingested and the age of the person. There are antidotes for atropine poisoning, but the affected person needs to get to a hospital as soon as possible to receive them.


moonlake profile image

moonlake 3 years ago from America

I have to check in the spring but I think I have that Bittersweet Nightshade growing in my garden. I have touched it and pulled it out because it gets all in my other plants thanks for this hub I know now to wear gloves and get that stuff out of the garden. Voted up.


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Hi, moonlake. Thanks for the vote! Bittersweet nightshade is a beautiful plant, but I wouldn't want it in my garden, either, since I have two dogs.


erorantes profile image

erorantes 3 years ago from Miami Florida

Thank you miss. Alicia. You did a good infomative article. You save a lot of life.God bless you.


AliciaC profile image

AliciaC 3 years ago from British Columbia, Canada Author

Thank you very much for such a kind comment, erorantes. I appreciate it.


Carrie 2 years ago

Mmn, I found out it tastes like peanuts at about age nine after mistaking it for a blackcurrent... Spat it out bloody quickly and yes, it was definitely deadly nightshade. Luckily I only got a very tiny amount in my mouth ;)


AliciaC profile image

AliciaC 2 years ago from British Columbia, Canada Author

It certainly was lucky that you only got a small amount of deadly nightshade in your mouth! Thanks for the comment, Carrie.


sam777777 profile image

sam777777 2 years ago from Queens, NY

Thanks for the information since I like to learn about the effect of plants on the body! Please write about other plants too.


AliciaC profile image

AliciaC 2 years ago from British Columbia, Canada Author

Hi, Sam777777. Thank you for the comment! I have actually written about the effects of other plant chemicals on the body. It's an interesting topic!


sam777777 profile image

sam777777 2 years ago from Queens, NY

I am definitely going to follow your hubs since I like the effects of plants on physical health. Health is my general niche as you can see from my hubs.


AliciaC profile image

AliciaC 2 years ago from British Columbia, Canada Author

Thanks, sam777777. I'm looking forward to reading your hubs, too.


Tammy 2 years ago

I found a pain relief product with BellaDonna in it. Should I avoid it?


AliciaC profile image

AliciaC 2 years ago from British Columbia, Canada Author

This is an important question, Tammy. You should ask your doctor about the product and shouldn't use it without medical advice.

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