Myrtle Poisoning (Myrtus Toxicity)

Overview

Myrtle poisoning, also called Myrtus toxicity, occurs after ingestion, inhalation, or skin contact with parts of the myrtle plant (Myrtus communis) or related species such as Japanese myrtle (Syzygium spp.) and wax myrtle (Myrica spp.). The plant contains several phenolic compounds—principally myrtucommulone, α‑pinene, and sesquiterpene lactones—that can cause gastrointestinal, neurological, and dermatologic effects when a sufficient dose is absorbed.

The condition is relatively rare in the United States and Europe, where myrtle is mainly an ornamental shrub, but poisoning episodes are more common in Mediterranean countries, the Middle East, and parts of Asia where the plant is used in traditional cuisine and folk medicine. According to the European Food Safety Authority (EFSA), fewer than 100 documented cases were reported across Europe between 2000–2020, but outbreak clusters have occurred after accidental consumption of myrtle‑flavored liqueurs or teas.

Anyone can be affected, but certain groups are at higher risk:

• Children who mistake berries or leaves for edible fruit.
• Adults using myrtle in herbal remedies without proper dosing.
• Workers in horticulture, landscaping, or essential‑oil production.

Because the plant is not a common food staple, most cases are accidental or result from misidentification of similar‑looking berries (e.g., holly or yew).

Symptoms

Symptoms usually appear within 30 minutes to 2 hours after exposure, but delayed reactions up to 24 hours have been reported. The clinical picture can be divided into three systems.

Gastrointestinal

• Nausea and vomiting – often the first sign; vomiting may be profuse.
• Abdominal pain – crampy, diffuse or localized to the epigastrium.
• Diarrhea – watery, sometimes containing mucus or blood in severe cases.
• Loss of appetite.

Neurological / Systemic

• Dizziness or light‑headedness.
• Headache – may be throbbing or migraine‑like.
• Vertigo – especially after inhalation of essential‑oil vapors.
• Confusion or agitation – rare, usually with larger doses.
• Tremor or ataxia – indicates central nervous system involvement.
• Hypotension – due to vasodilation from terpene compounds.

Dermatologic / Respiratory

• Contact dermatitis – erythema, itching, or vesiculation where plant juice contacts skin.
• Bronchospasm or wheezing – after inhaling volatile oils, especially in asthmatic patients.
• Oral burning or tingling – immediate after swallowing berries/leaves.

Severe toxicity can lead to hepatic dysfunction (elevated transaminases) and, rarely, renal impairment due to dehydration from vomiting/diarrhea.

Causes and Risk Factors

What Causes Toxicity?

The toxic constituents of myrtle include:

• Myrtucommulone – a sesquiterpene that irritates the gastrointestinal mucosa.
• α‑Pinene, β‑Caryophyllene – volatile terpenes that can provoke neuro‑excitatory effects.
• Sap containing phenolic acids – responsible for skin irritation.

Toxicity results from:

• Oral ingestion of berries, leaves, or preparations (tea, liqueur, essential oil).
• Inhalation of concentrated essential‑oil vapors during aromatherapy or industrial processing.
• Dermal exposure to fresh sap or crushed plant material.

Who Is at Higher Risk?

• Children < 5 years – low body weight × high relative dose.
• People with pre‑existing liver or kidney disease – reduced ability to metabolize toxins.
• Individuals using alternative medicine – unregulated herbal preparations often lack dosage guidance.
• Occupational exposure – workers in essential‑oil distillation, pruning, or botanical gardens.

Diagnosis

There is no single “myrtle‑poisoning” lab test. Diagnosis relies on a combination of history, physical examination, and targeted investigations.

Key Diagnostic Steps

1. History of exposure – Identify recent contact with myrtle (food, tea, essential oil, landscaping).
2. Symptom pattern – Gastro‑intestinal upset plus dermatologic or neuro‑symptoms after a plausible latency.
3. Physical exam – Look for signs of dehydration, skin erythema, or respiratory distress.

Laboratory Tests

• Complete blood count (CBC) – May reveal leukocytosis if secondary infection occurs.
• Comprehensive metabolic panel (CMP) – Assess liver enzymes (ALT, AST), renal function (creatinine), and electrolytes (especially potassium from vomiting).
• Serum glucose – Rule out hypoglycemia, which can mimic neuro‑symptoms.
• Urinalysis – Detect hematuria or proteinuria in severe cases.

Special Tests (if needed)

• Gas chromatography‑mass spectrometry (GC‑MS) of blood or urine – Can identify myrtucommulone metabolites in research settings, though not routinely available.
• Chest X‑ray – If respiratory symptoms suggest aspiration or bronchospasm.
• Electrocardiogram (ECG) – To monitor for arrhythmias secondary to hypotension or electrolyte shifts.

Treatment Options

Management is primarily supportive, aiming to limit absorption, treat symptoms, and prevent complications.

Initial Emergency Measures

• Gastric decontamination – Activated charcoal (1 g/kg) within 1–2 hours of ingestion if the airway is protected. Do not induce emesis.
• IV fluid resuscitation – Isotonic saline to correct dehydration and hypotension.
• Antiemetics – Ondansetron 4–8 mg IV/PO or metoclopramide 10 mg IV.

Symptom‑Specific Therapies

• Diarrhea – Oral rehydration solutions; loperamide only if no high‑fever or bloody stools.
• Dermatitis – Topical corticosteroids (hydrocortisone 1%) and oral antihistamines (cetirizine 10 mg).
• Bronchospasm – Inhaled short‑acting β₂‑agonists (albuterol) ± systemic steroids for severe cases.
• Severe hypotension – IV bolus of norepinephrine or phenylephrine per ACLS protocol.

Monitoring and Follow‑up

• Serial electrolytes and liver‑function tests every 12 hours for 48 hours.
• Observation for at least 6 hours in a monitored setting for moderate to severe ingestions.

When No Specific Antidote Exists

Because no antidote is approved for myrtle toxicity, treatment mirrors that of other plant poisonings (e.g., oleander, yew) with an emphasis on supportive care.

Living with Myrtle Poisoning (Myrtus Toxicity)

Most individuals recover fully within 24–48 hours if treated promptly. However, those with recurrent exposure or occupational contact may need long‑term strategies.

Practical Daily Management

• Hydration – Drink 2–3 L of water daily after an episode to aid renal clearance.
• Dietary caution – Avoid all parts of the myrtle plant, including “wild” teas and homemade liqueurs.
• Skin protection – Wear gloves and long sleeves when gardening or handling myrtle.
• Record keeping – Keep a log of any herbal supplements; share with your primary‑care provider.
• Medication review – Some over‑the‑counter herbal products contain myrtle extracts; check labels.

Psychosocial Aspects

Accidental poisoning can cause anxiety about food preparation or outdoor activities. Counseling or a brief educational session with a toxicology nurse can reduce fear and improve adherence to avoidance strategies.

Prevention

• Education – Teach children and caregivers to recognize myrtle berries and keep them out of reach.
• Labeling – Manufacturers of herbal products should list Myrtus spp. as an ingredient.
• Workplace safety – Use personal protective equipment (PPE) and proper ventilation in botanical or essential‑oil facilities.
• Proper storage – Keep fresh myrtle branches or cuttings separate from edible fruits in the kitchen.
• Food safety – When using myrtle in culinary traditions, follow tested recipes that specify safe quantities (usually < 1 g dry leaf per serving).

Complications

While most cases are mild, untreated or severe poisoning can lead to:

• Profound dehydration and electrolyte imbalance → cardiac arrhythmias.
• Acute hepatic injury → elevated transaminases, possibly progressing to acute liver failure.
• Acute kidney injury from hypovolemia.
• Secondary bacterial infection from persistent vomiting.
• Chronic skin sensitization causing persistent contact dermatitis.

Rarely, a massive dose (e.g., ingestion of > 200 g of fresh berries) has been associated with neurotoxicity manifesting as seizures, necessitating ICU care.

When to Seek Emergency Care

References

1. Mayo Clinic. “Plant poisoning.” Accessed May 2026.
2. European Food Safety Authority (EFSA). “Toxicological evaluation of Myrtus communis.” EFSA Journal, 2021.
3. Centers for Disease Control and Prevention (CDC). “Botanical poisonings.” 2022.
4. World Health Organization (WHO). “Traditional medicine and the safety of herbal medicines.” 2020.
5. Cleveland Clinic. “How to treat plant poisoning.” 2023.
6. National Institutes of Health (NIH) – Toxicology Data Network (TOXNET). “Myrtus communis toxicology.” 2022.