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Aconitum napellus
Toxic🐾Blauer Eisenhut · (Aconitum napellus)
Buttercup family (Ranunculaceae)
Description
With its deep blue, helmet-shaped flowers arranged in tall upright spikes, this buttercup-family perennial is among the most striking wildflowers of Central and Western European alpine and subalpine meadows. Deeply lobed, finger-like leaves rise on hairless stems reaching up to a metre, favoring damp ground along streams and mountain valleys, flowering from June through August. The root tuber concentrates diterpene alkaloids such as aconitine, making this plant one of the most toxic in Europe. Historically, heavily diluted tincture was applied externally for neuralgia, and homeopathic preparations used it in high dilutions; both applications are now largely obsolete. WARNING: every part of the plant is highly toxic, and even touching the flowers can cause numbness in the fingertips — never handle without gloves, no lay use whatsoever.
🌿 Risk of confusion — read before wild-harvesting!
LETHALLY TOXIC — ENTIRE PLANT, ESPECIALLY THE ROOT TUBER. Aconitum napellus is considered the most poisonous plant in Central and Western Europe. As little as 2–4 g of fresh root can kill an adult within 30–45 minutes; the lethal dose of pure aconitine is approximately 2 mg orally. Aconitine is absorbed percutaneously — merely touching the flowers can cause numbness in the fingertips. Poisoning symptoms usually appear within an hour: tingling and burning in mouth, face and extremities; nausea, vomiting, hypotension, bradycardia, ventricular arrhythmias. Death usually within 2–6 hours from respiratory paralysis or ventricular fibrillation. NO specific antidote available — therapy is symptomatic (antiarrhythmics, mechanical ventilation). In case of suspected poisoning: IMMEDIATELY call emergency services and poison control. NEVER touch without protective gloves. No lay use whatsoever. Even homeopathic mother tincture D1–D3 must be regarded as highly toxic.
External use only!
This plant must NOT be taken internally. Use only as compress, salve, or bath.
CONTRAINDICATED during pregnancy
Aconitine crosses the placental barrier and is embryotoxic. Any use of Aconitum napellus or aconite preparations below homeopathic D6 potency is absolutely contraindicated in pregnancy.
CONTRAINDICATED during breastfeeding
Aconitine and related diterpene alkaloids pass into breast milk and can trigger life-threatening cardiac arrhythmias and respiratory paralysis in the infant. Breastfeeding: strictly contraindicated.
CONTRAINDICATED for children
Children are extremely sensitive to aconitine. Even contact with flower pollen or chewing a single bloom can be life-threatening. The attractive blue-violet flower colour and turnip-shaped tuber pose particular danger. No application whatsoever — not even homeopathic potencies below D12 without medical instruction.
Critical drug interactions with:
Klasse-I-Antiarrhythmika (Chinidin, Procainamid, Flecainid, Lidocain) · Calciumkanalblocker (Verapamil, Diltiazem) · Herzglykoside (Digoxin, Digitoxin) · Beta-Blocker (Metoprolol, Bisoprolol, Propranolol)
Historical topical use of aconite tincture (Tinctura Aconiti) as an external remedy for neuralgia, trigeminal neuralgia, lumbago and rheumatic pain — applied to intact skin only, never to wounds. The analgesic effect rests on blockade of peripheral nerve fibres. Obsolete in Western medicine since the mid-20th century due to unpredictable systemic toxicity from transdermal absorption.
Preparation & dosage
Folk-medicinal use of aconite ointment (Unguentum Aconiti) for rheumatic joint complaints and sciatica by local rubbing. The historical application required completely intact skin without cuts or abrasions, since aconitine is rapidly systemically absorbed via broken skin. Due to documented fatalities from percutaneous poisoning, this application is considered obsolete and contraindicated today.
Preparation & dosage
Historical use of the tubers as arrow and murder poison in pre-Christian and ancient times: Celtic hunters may have used aconite extracts as arrow poison, the Roman Empire used it as poison against political opponents (banned for private cultivation under Emperor Trajan). In Germanic folklore the plant was 'wolfsbane', used to poison wolves — this tradition explains the English name. Documentation only, no application recommendation whatsoever.
Medieval use of aconite leaf extracts in so-called 'witches' ointments' together with henbane, datura and belladonna. The mixtures were applied to sensitive skin areas and were said to induce hallucinogenic 'flight dreams' — presumably through aconitine-induced paraesthesia combined with tropane-alkaloid effects. Pure ethnographic documentation, no application recommendation.
Preparation & dosage
Historical documentation only — do NOT use
These internal applications are historically documented. This plant is highly toxic — self-treatment can cause severe poisoning or death. For documentation only, explicitly NOT a recommendation.
Widespread 19th-century internal use of extremely low-dosed aconite tincture (typically 1–2 drops) as antipyretic and sedative in acute febrile states, pleurisy and pericarditis. The historical practice exploited aconitine's negative chronotropic effect to lower heart rate. Strictly obsolete today — no therapeutic window, documented fatalities from minimal dosing errors.
Preparation & dosage
Homeopathic use of Aconitum napellus (first proven by Samuel Hahnemann in 1805) for acute-onset fever, sudden fright, anxious restlessness and early inflammation. Usual dilution levels from D6 upwards (commonly D12, D30) contain no pharmacologically active aconitine amounts. Homeopathic medicinal products are licensed in Germany, Austria and Switzerland under medicinal-products law.
Preparation & dosage
In traditional Chinese medicine (TCM), the heat-detoxified root of related Aconitum species ('fùzǐ' from Aconitum carmichaelii) has been used for over 2,000 years for 'cold-yang-deficiency syndromes'. The Mawangdui manuscripts (168 BCE) already list aconite among the most frequent recipe ingredients. This application does NOT apply to the Central European Aconitum napellus, whose toxicity is barely reduced by heating. Pure documentation of historical practice.
Sources: [1]
⚠ External use only
LETHALLY TOXIC — ENTIRE PLANT, ESPECIALLY THE ROOT TUBER. Aconitum napellus is considered the most poisonous plant in Central and Western Europe. As little as 2–4 g of fresh root can kill an adult within 30–45 minutes; the lethal dose of pure aconitine is approximately 2 mg orally. Aconitine is absorbed percutaneously — merely touching the flowers can cause numbness in the fingertips. Poisoning symptoms usually appear within an hour: tingling and burning in mouth, face and extremities; nausea, vomiting, hypotension, bradycardia, ventricular arrhythmias. Death usually within 2–6 hours from respiratory paralysis or ventricular fibrillation. NO specific antidote available — therapy is symptomatic (antiarrhythmics, mechanical ventilation). In case of suspected poisoning: IMMEDIATELY call emergency services and poison control. NEVER touch without protective gloves. No lay use whatsoever. Even homeopathic mother tincture D1–D3 must be regarded as highly toxic.
Aconitine crosses the placental barrier and is embryotoxic. Any use of Aconitum napellus or aconite preparations below homeopathic D6 potency is absolutely contraindicated in pregnancy.
Aconitine and related diterpene alkaloids pass into breast milk and can trigger life-threatening cardiac arrhythmias and respiratory paralysis in the infant. Breastfeeding: strictly contraindicated.
Children are extremely sensitive to aconitine. Even contact with flower pollen or chewing a single bloom can be life-threatening. The attractive blue-violet flower colour and turnip-shaped tuber pose particular danger. No application whatsoever — not even homeopathic potencies below D12 without medical instruction.
Drug interactions
Klasse-I-Antiarrhythmika (Chinidin, Procainamid, Flecainid, Lidocain)
Class I antiarrhythmics are sodium channel blockers. Aconitine acts oppositely by persistent activation of voltage-gated sodium channels (binding to neurotoxin binding site 2 of the α-subunit). Combination leads to unpredictable interactions with risk of severe ventricular arrhythmias.
Calciumkanalblocker (Verapamil, Diltiazem)
Additive negative chronotropic and negative inotropic effects. Aconitine causes bradycardia and hypotension even at low doses; combination with calcium channel blockers can lead to third-degree AV block, asystole and cardiogenic shock.
Herzglykoside (Digoxin, Digitoxin)
Digoxin alters intracellular sodium and calcium homeostasis; concurrent aconitine exposure substantially increases proarrhythmic risk. Both substances raise intracellular calcium concentration via different mechanisms — synergy for ventricular tachyarrhythmias.
Beta-Blocker (Metoprolol, Bisoprolol, Propranolol)
Aconitine itself already induces bradycardia and AV conduction disturbances. Beta-blockers additively enhance this effect and can cause life-threatening bradyarrhythmia.
Lokalanästhetika (Lidocain, Procain, Bupivacain)
Local anaesthetics and aconitine both act on voltage-gated sodium channels but at different binding sites. Competition and unpredictable modulation of channel kinetics can lead to ventricular arrhythmias that are difficult to treat.
Contraindications
- Any self-administration of plant material (fresh plant, dried root, tea, homemade tincture) — absolutely contraindicated due to lack of therapeutic window
- Pre-existing cardiac arrhythmias (bradycardia, AV-block, long-QT syndrome, atrial fibrillation) — aconitine drastically increases arrhythmogenic potential
- Hypotension and cardiogenic shock — aconitine further lowers blood pressure
- Hepatic and renal insufficiency — delayed metabolism leads to accumulation of diterpene alkaloids
- Skin lesions, open wounds or eczema — drastically increased percutaneous absorption even from external applications
- Pregnancy, lactation, children and adolescents (see above)
Harvested part: whole plant
- Time of day:
- Excavation of root tubers after die-back of aerial parts in late autumn — alkaloid content peaks at this point. Exclusively for pharmaceutical or homeopathic processing by trained personnel.
- Drying:
- Drying in pharmaceutical facilities under controlled conditions at max. 50 °C. Never dry domestically — the odour during drying can already trigger poisoning symptoms.
- Time of day:
- Collection of foliage leaves shortly before or at the start of flowering for homeopathic mother tinctures. Alkaloid content of leaves significantly lower than tuber but still dangerous (approximately 1/10 of tuber concentration).
- Drying:
- Gentle drying at max. 40 °C in the shade; pharmaceutical processing required. Caution: aconitine does not volatilise and remains in the dried material.
- AconitineAlkaloidContent: 0.2-3 %
Main alkaloid of the root tuber; C19-norditerpene alkaloid; binds to neurotoxin binding site 2 of the α-subunit of voltage-gated sodium channels, preventing inactivation — persistent sodium influx causes depolarization followed by paralysis. Lethal oral dose approximately 2 mg.
- MesaconitineAlkaloidContent: Spuren bis 0.2 %
N-methyl analogue of aconitine; comparable cardiotoxic effect; contributes to overall toxicity of aconite extracts; pharmacologically closely related to aconitine.
- HypaconitineAlkaloidContent: 0.05-0.3 %
Diterpene alkaloid with slightly weaker toxicity than aconitine, still life-threatening; predominantly detected in tubers and lower stem sections.
- JesaconitineAlkaloidContent: Spuren
Structurally related companion alkaloid; smaller share of total alkaloid fraction; similar sodium channel action to aconitine.
- NapellinAlkaloidContent: Spuren
Amino-alcohol alkaloid from the root; pharmacologically considerably less active than the ester-diterpene alkaloids; indicator substance in phytochemical analysis.
- NeolineAlkaloidContent: Spuren
Companion alkaloid with weak antinociceptive activity in animal studies; not therapeutically used; contributes to chemical differentiation of Aconitum species.
- Aconitsäure (Aconitic acid)Phenolic acidContent: nicht quantifiziert
Tricarboxylic acid (trans-aconitic acid) as non-alkaloid constituent; pharmacologically without toxic significance; widespread in cell metabolism as a citric-acid-cycle intermediate.
- Flavonoide (Kaempferol- und Quercetin-Glykoside)FlavonoidContent: nicht quantifiziert
Secondary companion substances in the aerial plant parts; antioxidant activity; play no role in the plant's toxicology.
- [6]MonographCliniTox Giftpflanzen — Aconitum napellus aggr.: sehr stark giftig +++ (Institut für Veterinärpharmakologie und -toxikologie, Universität Zürich)(accessed: 2026-08-10)
- [4]BookPlants For A Future — Aconitum napellus(accessed: 2026-05-26)
- [5]BookMaud Grieve: A Modern Herbal — Aconite (botanical.com, 1931)(accessed: 2026-05-26)
- [1]WikipediaAconitum napellus — Wikipedia (EN)(accessed: 2026-05-26)
- [2]WikipediaBlauer Eisenhut — Wikipedia (DE)(accessed: 2026-05-26)
- [3]WikipediaAconitine — Wikipedia (EN)(accessed: 2026-05-26)