Plant poisoning symptoms may involve several different areas of the body, including the gastrointestinal, cardiac, neurologic, respiratory, dermatologic, and hematologic (blood) systems. Symptoms may occur within minutes or be delayed after ingestion, depending on the plant toxin and the amount. Do not wait for symptoms to appear. Immediately call Poison Control at 1-800-222-1222. You’ll speak with experts who can advise the next steps, such as contacting your doctor or going to the hospital.
Symptoms of highly toxic plant poisonings
Oleander, foxglove and lily-of-the valley contain cardiac glycosides. These substances act like digoxin, a heart medication derived from these plants. Signs and symptoms of poisoning include:
- Diarrhea
- Hyperkalemia (high levels of potassium in the blood)
- Irregular heart rate
- Vomiting
Azaleas, rhododendron and related plants contain grayanotoxins, which act on the nervous system and heart. Plant poisoning is usually the result of eating or chewing on the leaves. Tea brewed from the leaves and honey from the nectar are also toxic. Symptoms include:
- Slow heart rate (bradycardia)
- Slow respiratory rate
- Seizures
Continued effects resemble symptoms of cardiac glycoside poisoning (e.g., oleander).
Hemlock poisoning is from ingesting water hemlock (from the genus Cicuta). These plants contain cicutoxin, which acts on the central nervous system and causes seizures. Symptoms typically occur within 15 minutes. Fatal poisonings typically follow this sequence:
- Vomiting, nausea and diarrhea
- Dilated pupils
- Seizures
- Cardiac arrest
Nicotine from tobacco plants is a powerful chemical that acts on the nervous system. Coniine, from poison hemlock (different from water hemlock) is related to nicotine. These toxins produce what’s known as cholinergic syndrome. Signs and symptoms of ingesting nicotine-containing substances (such as eating a cigarette or from accidental exposure to nicotine replacement products including discarded nicotine patches) include:
- Constricted pupils
- Dry mouth (initially)
- Muscle weakness
- Paralysis
- Salivation
- Slow or rapid heart rate
- Tremor, seizures and coma
Green tubers and potato sprouts contain a compound related to nicotine. Ingesting a small amount causes gastrointestinal upset, but consuming large quantities can have nicotine-type effects. Signs and symptoms of toxicity include:
- Gastrointestinal symptoms, including nausea, vomiting, diarrhea; symptoms may be delayed 8 to 10 hours, up to 24 hours. Diarrhea may last 3 to 6 days.
- With large quantities, drowsiness, sweating, dilated pupils, and changes in blood pressure and heart rate
Jimson weed and belladonna (deadly nightshade) contain hyoscyamine (atropine) and scopolamine, which cause anticholinergic syndrome. Signs and symptoms include:
- Delirium
- Dilated pupils
- Rapid heart rate
- Urinary retention
- Warm, dry skin
Castor beans contain ricin, a very toxic substance that’s released when the bean is chewed. The highly concentrated ricin released from a single chewed bean can be fatal in a child. Signs and symptoms of castor bean poisoning include:
- Delirium
- Diarrhea, which may be bloody
- Seizures
- Vomiting
Other plant poisoning signs and symptoms include:
- Drowsiness
- Headache
- Stomachache or nausea
- Swelling
Serious symptoms that might indicate a life-threatening condition
In some cases, plant poisoning can be fatal. In addition to calling Poison Control at 1-800-222-1222, seek immediate medical care (call 911) if you, or someone you are with, have ingested plants or plant products known or suspected of being poisonous and develop any of these life-threatening symptoms including:
- Altered mental status, including delirium or loss of consciousness
- Difficulty breathing
- Irregular heart rhythm
- Severe weakness or paralysis
