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A few commonly grown plants are highly poisonous, and many are moderately poisonous (see Table 6: Poisoning: Moderately Poisonous Plants). Few plant poisonings have specific antidotes. Most plant ingestions, including the plants listed in Table Table 6: Poisoning: Moderately Poisonous Plants, result in minimal symptoms unless the leaves and other components are concentrated into a paste or brewed into a tea.

Highly toxic and potentially fatal plants include the following:

• Castor beans and jequirity beans
• Oleander and foxglove
• Hemlock

Castor beans and jequirity beans: Castor beans contain ricin, an extremely concentrated cellular poison. Jequirity beans contain abrin, a related and even more potent toxin. In both, the beans have a relatively impervious shell; thus, the bean must be chewed to release the toxin. However, the seed coating of the jequirity bean is often not intact, and simple bacterial digestion can release the abrin toxin.

Symptoms of either poisoning may include delayed gastroenteritis, sometimes severe and hemorrhagic, followed by delirium, seizures, coma, and death. Whole-bowel irrigation should be considered because it aims to remove all beans ingested.

Oleander and foxglove: These plants and lily of the valley (which is similar but less toxic) contain digitalis glycosides. Toxicity includes gastroenteritis, confusion, hyperkalemia, and arrhythmias. The serum digoxinSome Trade Names
DIGITEK
LANOXIN
Click for Drug Monograph
level can confirm ingestion but is not useful as quantitative information.

K levels are closely monitored. Hyperkalemia may respond only to hemodialysis. Ca is not recommended for arrhythmias. DigoxinSome Trade Names
DIGITEK
LANOXIN
Click for Drug Monograph
-specific fractionated antibody (Fab) fragments have been used to treat ventricular arrhythmias.

Hemlock: Hemlock poisoning (poison hemlock and water hemlock) can cause symptoms within 15 min.

Poison hemlock has nicotinic effects, beginning with dry mouth and progressing to tachycardia, tremors, diaphoresis, mydriasis, seizures, and muscle paresis. Rhabdomyolysis and bradycardia may occur.

Water hemlock seems to enhance γ-aminobutyric acid (GABA) activity. Symptoms may include gastroenteritis, delirium, refractory seizures, and coma.

Table 6
Moderately Poisonous Plants Plant Symptoms Treatment Aloe spp Gastroenteritis, nephritis, skin irritation Supportive care and irrigation with soap and water Azalea Cholinergic symptoms Supportive care and atropineSome Trade Names ATROPEN ATROPINE-CARE SAL-TROPINE Click for Drug Monograph Caladium spp Oral mucosal damage due to Ca oxalate crystals in leaves Supportive care and demulsification (eg, with milk or ice cream) Capsicum spp (peppers) Mucous membrane irritation and swelling Supportive care, irrigation, and possibly demulsification ColchicineSome Trade Names No US trade name Click for Drug Monograph (autumn crocus, meadow saffron, glory lily) Delayed gastroenteritis, multiple organ failure Supportive care and possibly, as a last resort, experimental colchicineSome Trade Names No US trade name Click for Drug Monograph -specific Fab fragments* Deadly nightshade Anticholinergic symptoms, hyperthermia, seizures, hallucinations Supportive care For severe hyperthermia or seizures, possibly physostigmineSome Trade Names No US trade name Click for Drug Monograph Dumbcane (dieffenbachia) Oral mucosal damage due to Ca oxalate crystals in leaves Supportive care and demulsification (eg, with milk or ice cream) Fava beans In patients with G6PD deficiency, gastroenteritis, fever, headache, hemolytic anemia Supportive care For severe anemia and poisoning, consideration of exchange transfusion Green potato and potato sprout Gastroenteritis, hallucinations, delirium Supportive care Holly berries Gastroenteritis Supportive care Jimsonweed Anticholinergic symptoms, hyperthermia, seizures, hallucinations Supportive care For severe hyperthermia or seizures, possibly physostigmineSome Trade Names No US trade name Click for Drug Monograph Lily of the valley Hyperkalemia, gastroenteritis, confusion, arrhythmias See discussion of digitalis preparations on see Heart Failure: Digitalis preparations Mistletoe Gastroenteritis Supportive care Nettle Local stinging and burning Supportive care Nightshade, common or woody Gastroenteritis, hallucinations, delirium Supportive care Philodendron spp Oral mucosal damage due to Ca oxalate crystals in leaves Supportive care and demulsification (eg, with milk or ice cream) Poinsettia Minor mucous membrane irritation Unnecessary Poison ivy Dermatitis See Dermatitis Pokeweed Mucous membrane irritation, gastroenteritis Supportive care Pothos Oral mucosal damage due to Ca oxalate crystals in leaves Supportive care and demulsification (eg, with milk or ice cream) Yew Gastroenteritis Rarely, seizures, arrhythmias, coma Supportive care *Available only in France. Fab = fractionated antibodies.

Last full review/revision April 2009 by Gerald F. O'Malley, DO

Content last modified April 2009