A few commonly grown plants are poisonous. Generally, poisoning is unlikely unless large quantities are ingested (for example, if the leaves and other components are concentrated into a paste or brewed into a tea) or the plant is highly toxic. Highly toxic and potentially fatal plants include castor beans, jequirity beans, poison hemlock, and water hemlock, as well as oleander and foxglove, which contain digitalis glycosides. Few plant poisonings can be cured by specific antidotes. (See also Overview of Poisoning.)
Many other plants cause less serious toxic effects (see table Moderately Poisonous Plants).
Castor and jequirity beans
Castor beans contain ricin, an extremely concentrated poison. Ricin has been used in assassination attempts and as a mass-casualty weapon. Castor bean seeds have a very tough shell so the bean must be chewed to release the poison.
Jequirity beans contain abrin, a related and more potent toxin than ricin. They can cause death after swallowing. Children can die after chewing only one bean.
Poisoning from castor beans or jequirity beans may cause severe vomiting and diarrhea (often bloody) after a delayed period. People later become delirious and have seizures. They may become comatose and die. Doctors sometimes try to flush the beans out of the stomach and intestines before they are absorbed.
Hemlock
Oleander, foxglove, and lily of the valley
Oleander, foxglove, and the similar but less toxic lily of the valley can cause vomiting and diarrhea, confusion, irregular heartbeat, and high levels of potassium in the bloodstream. These plants contain a substance very similar to the heart drug digoxin. Doctors sometimes treat people who are poisoned by these plants with a drug used to treat digoxin overdose.
Moderately Poisonous Plants
Plant |
Symptoms |
Treatment |
|
Aloe and related plants |
Gastroenteritis, kidney inflammation, and skin irritation |
Supportive care* if the plant is swallowed and flushing (irrigation) with soap and water if the skin is irritated |
|
Apricot, wild cherry, and peach pits and apple and other seeds (Prunus and Malus species), usually only if many seeds are chewed and swallowed |
Symptoms of oxygen deprivation, such as nausea, dizziness, difficulty concentrating, headache, vomiting, drowsiness, and poor coordination (similar to those of carbon monoxide poisoning) |
For serious poisoning, hydroxocobalamin given by vein and use of a cyanide antidote kit (including amyl nitrate given by inhalation and sodium nitrite and sodium thiosulfate given intravenously) |
|
Aristolochia (also called birthworts or pipevines) |
Formation of scar tissue in the kidneys |
Supportive care* |
|
Azalea |
Cholinergic† symptoms |
Supportive care* and atropine |
|
Caladium (also called elephant ear or angel's wings) and related plants |
Irritation of the mouth due to calcium oxalate crystals in the leaves |
Supportive care* and use of milk or ice cream to help dissolve the irritant |
|
Capsicum and related plants (peppers) |
Irritation of the skin and mucous membranes |
Supportive care* and flooding the affected area with water to wash the substance away (irrigation) |
|
Colchicine (autumn crocus, meadow saffron, or glory lily) |
Delayed gastroenteritis and malfunction (failure) of many organ systems Interference with the bone marrow's ability to produce blood cells and platelets, possibly causing anemia, infection, and/or bleeding |
Supportive care* |
|
Deadly nightshade |
Anticholinergic‡ symptoms, a high body temperature, seizures, and hallucinations |
Supportive care* For a very high body temperature or seizures, possibly physostigmine |
|
Dumbcane (dieffenbachia) |
Damage to the mouth due to calcium oxalate crystals in the leaves |
Supportive care* and use of milk or ice cream to help dissolve the crystals |
|
Fava beans |
In people with a deficiency of the enzyme G6PD (which protects red blood cells), gastroenteritis, fever, headache, and hemolytic anemia |
Supportive care* For severe anemia and poisoning, gradual removal and replacement of blood with equal volumes of fresh donor blood (exchange transfusion) considered |
|
Green potatoes and potato sprouts |
Gastroenteritis, hallucinations, and delirium |
Supportive care* |
|
Holly berries |
Supportive care* |
|
|
Jimsonweed |
Anticholinergic‡ symptoms, a high body temperature, seizures, and hallucinations |
Supportive care* For a very high body temperature or seizures, possibly physostigmine |
|
Licorice (raw plant) |
Too little potassium in the blood, high blood pressure, and swelling due to retention of fluid (edema) |
Supportive care* |
|
Lily of the valley |
Too much potassium in blood and abnormal heart rhythms (arrhythmias) |
Supportive care* and antibodies against digitalis |
|
Mistletoe |
Supportive care* |
|
|
Monkshood |
A low heart rate, abnormal heart rhythms, numbness and tingling, and weakness |
Supportive care* Sometimes sodium bicarbonate given intravenously |
|
Nettle |
Stinging and burning of the skin |
Supportive care* |
|
Nightshade, common or woody |
Gastroenteritis, hallucinations, and delirium |
Supportive care* |
|
Nightshade, deadly |
Anticholinergic‡ symptoms, a high body temperature, seizures, and hallucinations |
Supportive care* For a very high body temperature or seizures, possibly physostigmine |
|
Pennyroyal |
Damage to the liver (when severe, causing jaundice, confusion, and a tendency to bleed) |
Acetylcysteine |
|
Philodendron and related plants |
Damage to the mouth due to calcium oxalate crystals in the leaves |
Supportive care* and use of milk or ice cream to help dissolve the crystals |
|
Poinsettia |
Mild irritation if it touches the mucous membranes of the mouth, nasal passages, vagina, or urethra |
Unnecessary |
|
Poison ivy |
Inflammation of the skin (dermatitis) or mucous membranes |
Avoidance of known irritants; treatment of specific symptoms |
|
Pokeweed |
Irritation if it touches the mucous membranes of the mouth, nasal passages, vagina, or urethra |
Supportive care* |
|
Pothos |
Damage to the mouth due to calcium oxalate crystals in the leaves |
Supportive care* and use of milk or ice cream to help dissolve the crystals |
|
Yew |
Rarely, seizures, abnormal heart rhythms, and coma |
Supportive care* |
|
* Supportive care may include fluids given by vein (intravenously), treatments to maintain body functions (such as drugs to lower fever), drugs to increase blood pressure if it drops, and a ventilator. |
||
|
† Cholinergic symptoms include a slow heart rate, weakened contraction of the heart, dangerously low blood pressure, difficulty breathing (because airways are constricted), flushing, abdominal cramps, diarrhea, increased urination and salivation, watery eyes, increased sweating, and muscle cramping. |
||
|
‡ Anticholinergic symptoms include confusion, blurred vision, constipation, dry mouth, light-headedness, difficulty starting and continuing to urinate, and loss of bladder control. |
||
|
G6PD = glucose-6-phosphate dehydrogenase. |
||
More Information
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American Association of Poison Control Centers: 1-800-222-1222
Drugs Mentioned In This Article
| Generic Name | Select Brand Names |
|---|---|
sodium thiosulfate |
NITHIODOTE |
sodium bicarbonate |
No US brand name |
hydroxocobalamin |
CYANOKIT |
Acetylcysteine |
ACETADOTE |
Colchicine |
COLCRYS |
atropine |
ATROPEN |
digoxin |
LANOXIN |
