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Plant Poisoning

Indoor and outdoor plants are one of the leading causes of poisoning in young children.  In 2004, over 4% of all poisoning exposures reported to poison control centers in children less than 6 years of age involved plants.

Poisonous plants contain a wide variety of poisons and can cause a variety of medical problems, including stomach upset, mouth complaints, heart problems and liver and skin disease.

It is very important to know what types of plants have the potential of causing health problems if touched or swallowed by your child.

The purpose of this section is to help you become familiar with some of the more commonly encountered plants in order to lessen the risk of your child becoming poisoned.

Plants that cause a contact dermatitis (skin inflammation) such as poison ivy or poison oak are covered in detail elsewhere (click on Poison ivy).

It is safest to call your local poison control center (1-800-222-1222) ANYTIME a plant is ingested.

Plants causing illness similar to Cyanide Poisoning

1. Believe it or not, the leaves and seed kernels of peaches, apricots, apples, plums, and pears have a toxin which if swallowed can cause classic cyanide poisoning.

2. Another plant that contain the same toxin in it’s leaves, stems and seeds is the chokecherry (see photo called Chokecherry).  For more information on this plant, see http://extension.usu.edu/rangeplants/Woody/chokecherry.htm

3. Hydrangea, a very common ornamental plant, contain the same toxin in it’s leaves, but it would take eating many leaves for poisoning to occur (see photo called Hydrangea).

Signs and symptoms of poisoning are identical to cyanide poisoning and can include headache, dizziness, coma, seizure and poor heart function.

The good news is it takes a lot of seeds (50 apple seeds) or kernels (30 peach pits) before toxicity becomes a problem.

Plants causing Heart Problems

1. Cardiac Glycosides: Plants that contain substances that are similar in structure to the heart medication, digoxin.

They include foxglove (see photo called Foxglove), oleander (see photo called Oleander) and lily of the valley (see photo called Lily of the valley).

In general, all parts of the plants contain the toxin, with the greatest amount in the seeds, stems and roots.

Symptoms of poisoning are similar to digoxin poisoning with gastrointestinal illness (i.e. nausea, vomiting) and heart problems including a slowing down of the heart.

Mistletoe berries, and to a lesser extent the leaves and stems, contain a compound like digoxin that slow the heart. Other toxins in mistletoe induce nausea and vomiting. In fact, swallowing just a few mistletoe berries can cause serious problems for a toddler (see photo called mistletoe).

2. Grayanotoxin: This toxin is found in the leaves and flowers of rhododendrons (see photo called Rhododendrons), azaleas and mountain laurel (see photo called Mountain laurel).

Symptoms of poisoning include salivation, tearing, runny nose, vomiting, weakness, slow heart rate and low blood pressure.

3. Aconitine: This toxin is found in the monkshood which is native to northern temperate regions in North America.




The distinguishing characteristic of the Monkshood plant is it’s helmet shaped flowers (see photo called Monkshood).  The whole plant is poisonous especially the leave and roots.

Symptoms of poisoning include immediate numbness in the mouth, difficulty with speech, vomiting, low blood pressure and rhythm problems of the heart.

4. Yew: This plant is an evergreen shrub that possess needle like leaves with attractive red berries with partially exposed hard seeds (see photo called Yew and Yew 2).

All parts of the plant except the fleshy part of the red berry are poisonous.

Signs and symptoms of poisoning include slow heart rate and low blood pressure, headache, coma and seizures, bone marrow problems and numbness of the extremities.

Plants that cause many organs in the body to fail (multi-organ failure)

1. Ricin: This very potent toxin is found in castor beans of the castor bean plant (see photo called Castor bean plant).  All parts of these plants are toxic with the greatest concentration in the beans (see photo called Castor beans).

In order for the toxin to be released a child must chew on the bean rather than just swallow it whole.

Symptoms of poisoning develop within 4 to 10 hours and include abdominal pain, nausea, severe bloody diarrhea, and possibly liver and kidney disease.

2. Autumn crocus: This plant contains colchicine, a medication used to treat gout.
All parts of the plant are poisonous (see photo called Autumn crocus).

If significant ingestion occurs gastrointestinal symptoms should be present within 6 hours and
include abdominal pain, nausea, vomiting and diarrhea that may be bloody.  Symptoms may progress to involve the blood cells, the heart, lungs and brain.

Plants causing Central nervous system (Brain) Toxins

Water Hemlock: This plant is found along marshes and lakes.
All parts of the plant are poisonous (see photo called Water hemlock).

Signs and symptoms of poisoning develop within 30 – 60 minutes after exposure and initially include stomach upset followed rapidly by the development of seizures that often do not respond to standard therapy.

Plants that contain Calcium oxalate

Plants in this group include dieffenbachia (dumbcane) (see photo called Dumbcane), philodendron (see photo called Philodendron), caladium (see photo called Caladium) and elephant ears (see photo called Elephant ears).

Exposures to plants containing oxalate crystals, such as Philodendron and Dieffenbachia, are among the most common toxic plant exposures reported to poison centers in the US.  The majority of oxalate plant exposures occur in children younger than 5 years while sampling houseplants in the home.

Calcium oxalate are needlelike crystals that produce pain and swelling when they contact lips, tongue, sides of the mouth, eyes and skin.

General signs and symptoms of poisoning include reddening and itchiness of the skin after the plant is touched.  After the chewing of a leaf, the crystals cause pain and swelling of the mouth.  Severe cases may progress to salivation, loss of speech, trouble swallowing; however, severe cases are extremely rare.  Most cases result in mild symptoms that resolve with cold milk.

Plants that cause gastrointestinal irritation (stomach upset)

1. Plants of this category include baneberry (see photo called Baneberry), english ivy (see photo called English ivy), pokeweed (see photo called Pokeweed and Pokeweed 2) and buckthorn (see photo called Buckthorn).

Symptoms include abdominal pain, diarrhea which may be bloody and vomiting.

2. Holly berries contain ilex acid, which irritates the stomach and causes nausea, vomiting, and diarrhea.  A child usually must swallow 20 or more holly berries before serious problems develop (see photo called Holly berries).
3. Plants that contain the toxin solanine include common nightshade (see photo called Common nightshade), jerusalem cherry (see photo called Jerusalem cherry) and tomato and potato plants.
“Green” potatoes are a common cause of human poisonings.

Symptoms of nausea, vomiting, diarrhea and abdominal pain typically begin 2 – 24
hours after ingestion and may last several days.

Plants that cause agitation, hallucinations and large pupils

Plants in this category include deadly nightshade (see photo called Deadly nightshade), jimsom weed (see photo called Jimson weed and Jimson weed 2), moonflower (see photo called Moonflower) and angel’s trumpet (see photo called Angel’s trumpet).

The plants contain varying amounts of toxins called atropine, scopolamine and hyoscyamine.
Symptoms include fast heart rate, large pupils, dry reddened skin, decreased bowel
sounds, inability to urinate, hallucinations, agitation and seizures.

Plants that cause nicotine-like poisoning

Poison Hemlock: This plant was used in ancient times as a means of execution, alleged to have
caused the death of Socrates.

The plant grows in woods and along roads throughout the U.S. and has fern like leaves (see photo called Poison hemlock)

Toxicity is similar to nicotine poisoning and typically has two phases.
The first phase consists of a fast heart rate, tremors, sweating and seizures.
Severe cases will go on the develop paralysis, coma, breathing problems and a slow heart rate.

Non-Toxic Plants

The plants listed below are considered non-toxic (safe and not poisonous). Illness from
eating or touching these plants is not likely. However, any plant may cause a reaction in certain people.

African Violet
Butterfly bush
Christmas Cactus
Monkey grass

* It is a myth that the poinsettia plant is poisonous. This myth had its origin in 1919 when a two-year-old child of an Army officer stationed in Hawaii died of poisoning, and the cause was incorrectly assumed to be a poinsettia leaf.

Based on animal experiments, a 50 pound child would have to eat more than 1.25 lbs. of poinsettia bracts (about 500 to 600 leaves) to exceed the experimental doses for toxicity (see photo called Poinsettia)

For a more detailed list of non-toxic as well as toxic plants, go to http://www.cardinalglennon.com/internet/home/glennon30.nsf/graphics/Toxic+and+NonToxic+Plants.pdf/$file/Toxic+and+NonToxic+Plants.pdf

Plant Safety

To help prevent plant poisonings, follow these 12 safety tips:

  1. Before buying a new plant, have the store label the plant with the common and Latin name.  Poison Center staff cannot identify a plant from a plant description given over the phone.
  2. Know the names of all the plants in your home and yard. If you need help
    identifying a plant, take a piece of it to a nursery, florist, or your county
    extension agent.
  3. Show grandparents and babysitters where to find the plant names. Grandparents and babysitters who care for your child away from your home should also know the names of the plants in their homes.
  4. Keep house plants, seeds, and bulbs out of the reach and sight of children and
  5. Teach your children to never put any part of a plant into their mouths.
  6. Do not eat wild plants or mushrooms. Cooking poisonous plants does not make them
    safe to eat.
  7. Never use anything prepared wild from nature as a “natural” medicine or tea.
  8. Keep weed and bug killers in a locked cabinet, out of the reach of children and
    pets. Never put them in bottles used for drinking.
  9. Wear gloves and protective clothing when handling plants that can be irritating to the skin. Wash hands and clothes well afterwards.
  10. Smoke from burning poisonous plants (especially poison oak) can irritate the eyes, nose, throat and lungs.
  11. Keep the telephone number of your local Poison Control Center on or near your
    telephones (1-800-222-1222).
  12. If any part of a plant is eaten, remove as much of the plant as possible from
    the mouth and call your local Poison Control Center right away!  Do not wait for the
    victim to look or feel sick.

For information on plants that are poisonous for your pets go to