Linda Crampton has an honors degree in biology. She is very interested in plant chemicals and their actions and benefits in the human body.
A Dangerous 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 by a doctor atropine has important medical applications.
Deadly nightshade is native to Europe, North Africa, and Western Asia, but the plant grows in North America as well. It's found in woods or on disturbed ground. It's a herbaceous perennial that can be impressively tall. It's said to generally range from two to three feet in height but to sometimes be four or even five feet tall. 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 devil’s cherries because although the berries look appetizing they are actually very toxic.
Possible Symptoms of Deadly Nightshade Poisoning
Eating any part of the deadly nightshade dangerous. According to the Missouri Botanical Garden, simply touching the plant may be harmful if the skin has cuts or other wounds. Intact skin in good condition should act as a barrier. It's advisable to wear gloves if the plant has to be handled, however.
There are many possible symptoms of deadly nightshade poisoning. As mentioned above, they may be caused by other problems. The symptoms may include:
- rapid heartbeat
- dry mouth
- slurred speech
- light sensitivity
- blurred vision
- inability to urinate
- loss of balance
- flushed skin
- a rash
- memory loss
Severe poisoning may cause paralysis, a coma, and respiratory failure. If any part of the plant is ingested by a person or a pet, a doctor or a veterinarian should be visited immediately.
The Poisonous Berries of Deadly Nightshade
How Does Atropine Affect the Body?
Our nervous system produces acetylcholine, which is a type of excitatory neurotransmitter. The neurotransmitter is released from the end of a stimulated neuron (or nerve cell) in order to stimulate the next neuron and transmit a nerve impulse. Acetylcholine must bind to a receptor on the second neuron 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. It 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.
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 autonomic 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 produces the opposite effects and is sometimes called the “rest and digest” system. It 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 the 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 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 chemical 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.
Effects of Atropine on the Eyes
A safe concentration of atropine is used in eye drops to make the pupils dilate so that a doctor can examine the inside of the eyes properly. The pupil is an opening in the middle of the iris that allows light to enter the eye. Pupils may stay dilated for several days after an atropine treatment.
It’s said that in earlier times Italian women used belladonna to dilate their pupils in an attempt to themselves look more attractive. The name “belladonna” is derived from the words meaning “beautiful lady” in Italian.
The vision of the women who used belladonna may have become blurred. Atropine can inhibit accommodation—the process in which the lens changes shape to focus on objects at different distances from the eye. The women may have experienced additional side effects due to an unsafe concentration of the chemical. The atropine used in medical eye drops today is present at a far lower concentration than in the plant.
Digestive Tract Effects
Food is passed along the digestive tract by wave-like contractions in the intestinal wall known as peristalsis. Acetylcholine binds to muscarinic receptors in the muscles of the intestinal wall, triggering the muscles to contract. When atropine attaches to the receptors, it blocks acetylcholine. This calms the 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 which surrounds the passageway that 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.
Other Uses of Atropine
Atropine decreases the production of body secretions, including saliva, mucus, and sweat. It's been used in cough syrups to help clear the airways.
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 neurotransmitter continues to stimulate nerves. Atropine is used as an antidote to the nerve agents. It blocks the acetylcholine receptors, preventing the acetylcholine from reaching the nerves. Military personnel may carry an atropine auto-injector to protect themselves from chemical weapons.
The Bittersweet Nightshade Plant
The bittersweet nightshade, or Solanum dulcamara, is sometimes known as deadly nightshade. It's poisonous and can occasionally 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 that is native to Europe and Asia but is widespread in North America. Like the deadly nightshade, the bittersweet nightshade belongs to the plant family known as the Solanaceae.
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.
Toxins in Bittersweet Nightshade
All parts of the bittersweet nightshade are poisonous. One of the toxic chemicals in the plant is solanine, which is often found in green potatoes. The potato plant is another member of the family Solanaceae. The bittersweet nightshade also contains dulcamarine, which has quite similar effects to atropine.
In a way, the bittersweet nightshade plant is more dangerous than deadly nightshade, even though it's less poisonous. It's more common than the deadly nightshade, at least where I live, so children, pets, and livestock are more likely to encounter it. It also has more attractive flowers and more colourful berries, which may attract attention.
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.
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.
- Atropa belladonna facts from the Missouri Botanical Garden
- Information about the deadly nightshade plant from North Carolina State University
- Atropine Ophthalmic facts from the NIH (National Institutes of Health)
- Chemicals that affect the nervous system (including atropine) from openstax.org and Rice University
- Nerve agents, acetylcholine, and atropine effects from the University of Washington
- Bittersweet nightshade identification and control from the government of King County, Washington
This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.
Questions & Answers
Question: Are nightshade flowers always purple, or can they also be white?
Answer: As far as I know, the flowers are always purple. The black nightshade (Solanum nigrum) does have white flowers, however. It's sometimes confused with deadly nightshade.
Question: Is stepping on a clump of deadly nightshade harmful?
Answer: If deadly nightshade contacts cuts in the skin, it can irritate. As far as I know, stepping on the plant while wearing shoes isn't harmful, however. It might be a good idea to wash the soles of the shoes without directly touching them so that any toxin isn't transported into a home, though.
Question: I sleep near nightshades and I have strong dreams. So did another person and he did too. The smell is strong. They are about 20 feet away. Is it dangerous to sleep there long term?
Answer: I’m not sure what nightshade plant you are referring to. It doesn’t sound like deadly nightshade. It could be jimsonweed (Datura stramonium), which belongs to the nightshade family and is said to have a strong smell. If it is this plant, it’s toxic. It would be a good idea to very carefully remove the plant, taking all safety precautions, or to ask an expert to remove it. It would also be a good idea to avoid the plant wherever it grows.
Question: Is it safe to handle deadly nightshade?
Answer: Deadly nightshade is dangerous when eaten. It's advisable to wear protective gloves when handling it for two reasons. One is that the plant may cause irritation if the person has a cut or a graze. Another is that if food is eaten after handling the plant without gloves, the food may become contaminated with harmful material from the nightshade.
Question: Can Belladonna cause severe skin rash?
Answer: Not as far as I know. It's true that people have individual sensitivities to particular chemicals and that some people may experience worse symptoms than others when exposed to the chemicals. Deadly nightshade is known for its internal effects rather than its external ones, though. It's still a good idea to clear any deadly nightshade from a property with care and while wearing protective gloves.
Question: What happens if you put the juice of the nightshade in the eye?
Answer: Never do this! Most likely what will happen is damage to the eye. Deadly nightshade can irritate the skin. The eyes are even more sensitive than the skin and can be seriously and sometimes permanently damaged by substances that enter them, including the liquid from deadly nightshade. When doctors use or prescribe atropine eye drops, the atropine is pure and is present in a safe concentration and amount. This isn't the case in deadly nightshade.
Question: Is the plant always deadly? Can it be mildly poisonous?
Answer: No, the plant is not always deadly, but it’s very poisonous and always has the potential to cause serious harm. As in many other poisonous plants, the effects depend on the amount of poison that a person is exposed to as well as their individual susceptibility to it. Even small doses of deadly nightshade may be dangerous, however. The plant should always be treated with respect. Anyone exposed to the poison should seek medical treatment. Whether a person survives or not may very well depend on whether they get medical treatment and on how soon they get this treatment.
© 2010 Linda Crampton
Linda Crampton (author) from British Columbia, Canada on May 05, 2020:
Thank you for sharing the interesting information, Melissa.
Melissa Artemisia on May 03, 2020:
I'm a big fan of Nightshades and grow quite a few of them since I have no kids or dogs. I'm referring to the question about the "strong smelling Nightshade, 20 ft away." You suggested it was Datura. I would bet it's Datura's relative, Brugmansia or Angels Trumpet. They have an intensely strong smell. I grow 2 of them. They are poison to ingest,and you should wash your hands if you touch them, but the smell isn't dangerous.The smell is sweet and intense, like Night Blooming Jasmine An old Eastern Indian story stated that if you fell asleep under an Angel's Trumpet you'd have fabulous dreams and never wake up.
Linda Crampton (author) from British Columbia, Canada on August 20, 2019:
I’m sorry about the problem that you're experiencing, but I very much doubt that it’s due to deadly nightshade. Any skin problems caused by the plant would appear soon after contact, not three weeks later. I think you should make sure that you’ve identified the plant correctly and also consult a doctor if necessary to find an explanation and effective treatment tor the rashes.
Madelaine on August 19, 2019:
Since I’ve moved into my new home 3 summers ago I’ve been battling this plant. My back yard is infested and just can’t seem to get rid of it. When ever I or my son and even my neighbors have been touched with this plant it takes 3weeks before blister type rash breaks out, it is impossible to get rid of the rash and even with cortisone cream it takes weeks. This plant is my living nightmare. 3 weeks ago I noticed while walking out of the pool that there was a plant growing on the ladder step and well 3 weeks later my feet and between my toes are covered. So what ever you do stay away from this plant and get rid of it
Linda Crampton (author) from British Columbia, Canada on July 28, 2019:
I doubt it. People have different sensitivities to chemicals, though. A poison control centre could give you advice.
Lynn R on July 27, 2019:
If you accidentally touch Deadly Nightshade without gloves and you have no cuts but then wash your hands can you be affected in any way
Linda Crampton (author) from British Columbia, Canada on September 19, 2018:
Hi, Mary. Thanks for the visit. I think belladonna is an interesting plant, even though it's dangerous.
Mary Norton from Ontario, Canada on September 19, 2018:
I don't think I have visited this hub before. It is interesting to know what plants can harm us. This Belladonna looks beautiful.
Linda Crampton (author) from British Columbia, Canada on March 04, 2018:
Hi, Birgitta. I can't recommend anything, since I'm a science writer, not a health professional. Someone who has ingested berries should get immediate medical attention. To find out if anything else can be done to help them, you should ask your doctor or a poison control centre for advice.
Birgitta Blickman on March 04, 2018:
Nightshade or Belladonna is a beautiful flower and berries would attract most people especially those with poor eye sight. So if someone were to ingest several ... a handful of the berries would it be fatal? If hiking with someone what would I do to provide immediate help while waiting for medical assistance? Seems like hikers should carry items to counteract any accidental poisonous plant exposure. What do you recommend.
Linda Crampton (author) from British Columbia, Canada on April 14, 2017:
Hi, Ona. Homeopathic products generally contain extremely dilute concentrations of the active substance.
Ona Wheeler on April 14, 2017:
If it's so deadly then why do homeopathic remedies use it
Linda Crampton (author) from British Columbia, Canada on October 14, 2014:
This is an important question, Tammy. You should ask your doctor about the product and shouldn't use it without medical advice.
Tammy on October 14, 2014:
I found a pain relief product with BellaDonna in it. Should I avoid it?
Linda Crampton (author) from British Columbia, Canada on June 28, 2014:
Thanks, sam777777. I'm looking forward to reading your hubs, too.
Satvinder S. Sihra from Queens, NY on June 28, 2014:
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.
Linda Crampton (author) from British Columbia, Canada on June 28, 2014:
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!
Satvinder S. Sihra from Queens, NY on June 28, 2014:
Thanks for the information since I like to learn about the effect of plants on the body! Please write about other plants too.
Linda Crampton (author) from British Columbia, Canada on January 11, 2014:
It certainly was lucky that you only got a small amount of deadly nightshade in your mouth! Thanks for the comment, Carrie.
Carrie on January 11, 2014:
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 ;)
Linda Crampton (author) from British Columbia, Canada on November 29, 2013:
Thank you very much for such a kind comment, erorantes. I appreciate it.
Ana Maria Orantes from Miami Florida on November 29, 2013:
Thank you miss. Alicia. You did a good infomative article. You save a lot of life.God bless you.
Linda Crampton (author) from British Columbia, Canada on November 26, 2013:
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.
moonlake from America on November 26, 2013:
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.
Linda Crampton (author) from British Columbia, Canada on May 04, 2013:
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.
LydiaH on May 04, 2013:
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?
Linda Crampton (author) from British Columbia, Canada on January 21, 2013:
Deadly nightshade is very poisonous and may kill people. Eating any part of the plant is extremely dangerous. It should never be eaten.
shakes on January 21, 2013:
i want to eat it