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Yew Poisoning (Taxus spp. Toxicity)

Overview

Yew poisoning occurs after ingestion or, rarely, significant skin contact with any part of the yew tree (Taxus species). All parts of the plant—except the fleshy red arils that surround the seeds—contain toxic alkaloids called taxine alkaloids. These compounds block the calcium channels in heart muscle cells, leading to potentially fatal cardiac arrhythmias. Yew poisoning most often affects children who mistakenly eat the foliage, but adults can be poisoned intentionally (e.g., suicide attempts) or unintentionally while foraging for “wild” edible plants.

Although yew trees are common in temperate gardens and parks across North America, Europe, and parts of Asia, actual poisoning cases are relatively rare. According to the U.S. Centers for Disease Control and Prevention (CDC), there are <≈ 200 reported yew toxicity incidents in the United States each year, with a mortality rate of 10‑25 % when treatment is delayed [1].

Symptoms

Symptoms typically appear within 30 minutes to 2 hours after ingestion and progress in three phases.

Early (0‑2 h)

• Nausea and vomiting – often profuse and may contain blood.
• Abdominal pain – cramping, sometimes with diarrhea.
• Metallic or bitter taste – characteristic of taxine exposure.
• Salivation – excessive drooling.

Cardiac Phase (2‑6 h)

• Bradycardia – unusually slow heart rate (<60 bpm).
• Hypotension – low blood pressure causing dizziness or fainting.
• Arrhythmias – including atrial fibrillation, ventricular tachycardia, or heart block.
• Chest pain or tightness.

Late Phase (6‑24 h)

• Neurological signs – confusion, seizures, or coma in severe cases.
• Respiratory depression – shallow breathing that may require ventilation.
• Renal impairment – elevated creatinine from hypoperfusion.

Because taxine alkaloids act directly on the heart, the most dangerous sign is a rapidly deteriorating cardiac rhythm. If any of the cardiac symptoms appear, emergency care is mandatory.

Causes and Risk Factors

Yew poisoning is caused by ingestion of taxine‑containing plant material.

Primary sources

• Leaves and stems – highly concentrated.
• Seeds – contain lower amounts, but the surrounding red arils are non‑toxic and may lure children to the truly poisonous seed.
• Cut branches or decorative wreaths that include yew foliage.

Risk factors

• Age – children <5 years are most vulnerable due to curiosity and smaller body mass.
• Mental health conditions – depression or suicidal ideation increases intentional ingestion.
• Foraging habits – lack of botanical knowledge when gathering wild edibles.
• Cultural practices – some traditions use yew berries for ornamental purposes, increasing exposure.
• Occupational exposure – landscapers, horticulturists, or funeral‑home workers who handle yew cuttings.

Diagnosis

Prompt recognition is crucial because laboratory confirmation may take time.

Clinical assessment

• History of possible yew exposure (direct questioning of patient or witnesses).
• Physical exam focusing on cardiovascular status – heart rate, rhythm, blood pressure.
• Neurological exam for consciousness level.

Laboratory tests

• Serum electrolytes – especially potassium and calcium, which can become abnormal.
• Cardiac enzymes (troponin, CK‑MB) – to assess myocardial injury.
• Blood gas analysis – detects metabolic acidosis.
• Taxine assay – specialized LC‑MS/MS testing; available only at reference labs, not useful for acute decision‑making.

Electrocardiogram (ECG)

ECG is the most valuable diagnostic tool. Typical findings include:

• Sinus bradycardia.
• Prolonged PR interval.
• Widened QRS complexes.
• Ventricular ectopy or torsades de pointes.

Imaging (if needed)

• Chest X‑ray – to evaluate pulmonary edema in severe cases.
• Echocardiogram – to assess cardiac function if hemodynamic instability persists.

Treatment Options

There is no specific antidote for taxine alkaloids; treatment is supportive and focuses on stabilizing the heart and preventing further absorption.

First‑aid measures (pre‑hospital)

• Do NOT induce vomiting – the plant material can cause further esophageal injury.
• Activated charcoal (1 g/kg, up to 100 g) administered within 1‑2 h of ingestion can bind remaining toxin.
• Call emergency medical services immediately.

Emergency department care

• Cardiac monitoring – continuous ECG, pulse oximetry, and blood pressure.
• Intravenous fluids – isotonic saline to maintain perfusion.
• Atropine for symptomatic bradycardia (0.5 mg bolus, repeat every 3–5 min up to 3 mg).
• Vasopressors (e.g., norepinephrine) if hypotension persists despite fluids.
• Anti‑arrhythmic therapy – magnesium sulfate (2 g IV) for torsades; amiodarone can be used for ventricular tachycardia.
• Temporary cardiac pacing – indicated when bradycardia is refractory to drugs.
• Advanced cardiac life support (ACLS) – as per American Heart Association guidelines if cardiac arrest occurs.

Gastrointestinal decontamination

Beyond activated charcoal, whole‑bowel irrigation (via nasogastric tube) may be considered in massive ingestions, but data are limited.

Supportive care

• Oxygen therapy or mechanical ventilation for respiratory failure.
• Renal replacement therapy if severe acute kidney injury develops.
• Monitoring for delayed arrhythmias for at least 24 h after symptom resolution.

Discharge and follow‑up

• Patients who remain arrhythmia‑free for 24 h and have stable vitals can be discharged with cardiology follow‑up.
• Education on avoiding future exposure is essential.

Living with Yew Poisoning

Most surviving patients recover fully, but some may experience lingering cardiac concerns.

Monitoring

• Obtain a follow‑up ECG 1–2 weeks after discharge.
• Annual cardiac evaluation if any residual conduction abnormality was noted.

Lifestyle adjustments

• Avoid strenuous exercise for 2‑4 weeks after an event, as increased heart demand could provoke arrhythmias.
• Maintain a heart‑healthy diet (low sodium, adequate potassium, omega‑3 fatty acids).
• Stay hydrated; dehydration can exacerbate cardiac irritability.

Psychological support

For intentional ingestions, referral to mental‑health services is vital. Cognitive‑behavioral therapy and, when indicated, antidepressant medication reduce recurrence risk.

Prevention

• Education – Teach children that “green, leafy plants are not food.” Include yew in school safety curricula.
• Garden safety – Plant yew in areas inaccessible to children or pets; label ornamental yew shrubs.
• Proper disposal – When pruning yew, immediately bag and discard foliage in a sealed container.
• Foragers – Carry a reliable field guide; when in doubt, leave the plant untouched.
• Mental health screening – Routine assessment for depression in primary care can prevent intentional ingestions.

Complications

If treatment is delayed or inadequate, taxine toxicity can lead to:

• Fatal cardiac arrest (most common cause of death).
• Persistent conduction defects requiring permanent pacemaker implantation.
• Myocardial infarction from prolonged ischemia.
• Acute kidney injury secondary to hypotension.
• Neurological sequelae—cognitive deficits after prolonged hypoxia.
• Secondary infections from invasive procedures (e.g., central lines).

When to Seek Emergency Care

References

1. Centers for Disease Control and Prevention. “Poisoning Surveillance Data.” 2022.
2. Mayo Clinic. “Yew (Taxus) poisoning.” Updated 2023.
3. World Health Organization. “Poisoning and toxicology fact sheet.” 2021.
4. Cleveland Clinic. “Management of Plant Toxin–induced Cardiac Arrhythmias.” 2022.
5. National Institutes of Health. “Taxine Alkaloid Toxicity.” 2024.

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