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Laburnum anagyroides
Toxic🐾Gemeiner Goldregen · (Laburnum anagyroides)
Legume family (Fabaceae)
Description
In May and June this legume-family tree hangs heavy with golden-yellow flower chains that later form pea-like pods with dark seeds — and it is exactly this resemblance to edible peas that makes laburnum the most common cause of serious plant poisoning in children across Central Europe. The culprit is the alkaloid cytisine, reaching up to three percent in the seeds, which acts on the same receptor as nicotine. Curiously, this isolated alkaloid — never the plant itself — has been used pharmaceutically since the 1960s as the smoking-cessation drug Tabex® and now sits on the WHO List of Essential Medicines. Historically, heavily diluted seed preparations were also used against whooping cough, and during the Second World War soldiers short of tobacco resorted to dried laburnum seeds as a risky substitute. As a plant, though, laburnum remains highly dangerous: as few as three or four unripe pods, or 15 to 20 seeds, are potentially fatal to an adult. If a child is suspected to have eaten any part, call emergency services immediately — there is no specific antidote.
🌿 Risk of confusion — read before wild-harvesting!
10 flowers are considered potentially fatal; the threshold for children is substantially lower. Fatal poisonings are relatively rare thanks to rapidly setting in emesis but are documented. Risk of confusion: unripe pods may be mistaken by children for pea, bean or black-locust pods.
External use only!
This plant must NOT be taken internally. Use only as compress, salve, or bath.
CONTRAINDICATED during pregnancy
Cytisine is teratogenic according to animal experiments and older human data — it crosses the placental barrier and can cause fetal malformations (skeletal anomalies; the related "crooked calf disease" in cattle, caused by anagyrine, serves as a model). Any oral use of cytisine (including Tabex) as well as any exposure to plant parts during pregnancy is strictly contraindicated.
CONTRAINDICATED during breastfeeding
Cytisine presumably passes into breast milk (lipophilic, low molecular weight) and may induce nicotinic effects (tachycardia, vomiting, seizure tendency) in the infant. Breastfeeding: strictly contraindicated.
CONTRAINDICATED for children
Children are by far the most frequently affected risk group. As few as 2–3 seeds can trigger severe poisoning symptoms in a child, 5–7 seeds can be lethal. Laburnum shrubs in gardens, playgrounds, school yards and parks should — where removal is not possible — be fenced off and labelled. Parents and educators must inform children about the toxicity. If ingestion of seeds or pods is suspected: IMMEDIATELY call poison control.
Critical drug interactions with:
Nikotinersatztherapie (Pflaster, Kaugummi, Lutschtabletten, Inhalator) · Vareniclin (Champix®/Chantix®) · Bupropion (Wellbutrin®/Zyban®)
Historical external use as botanical insecticide: laburnum seeds were used — analogously to tobacco leaves — as nicotinergic sprays against aphids, bugs and caterpillars (PFAF documents "nicotine-like insecticidal qualities"). No longer recommended today due to percutaneous absorption of cytisine through the user's hands — purely of documentary value.
Preparation & dosage
Sources: [4]
Folk belief and sympathetic magic: in parts of Central and Southern Europe laburnum was credited with apotropaic ("warding off") magic — branches were hung over stable doors against the "evil eye" or used against witchcraft. Wikipedia (EN) notes: "The plant is believed to have magic properties in some regions." Pure cultural/folklore phenomenon — no medical relevance.
Preparation & dosage
Sources: [1]
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.
Pharmaceutical use of the isolated alkaloid cytisine (NOT the plant itself!) as a smoking cessation aid — marketed as Tabex® by Sopharma (Bulgaria) since 1964. Cytisine acts as a partial agonist at the α4β2 nicotinic acetylcholine receptor (nAChR), analogous to varenicline. The NEJM trial by West et al. (2011) showed a 12-month abstinence rate of 8.4 % with cytisine vs. 2.4 % with placebo; Walker et al. (2014) demonstrated non-inferiority to nicotine replacement therapy. Cytisine is on the WHO List of Essential Medicines (2025). The plant itself is NOT therapeutically usable due to unpredictable alkaloid variability — only the standardized pure alkaloid in 1.5 mg tablets under medical supervision.
Preparation & dosage
Historical folk medicinal use of laburnum seeds in highly diluted form for whooping cough (pertussis) and asthma in the 18th and 19th centuries — documented by PFAF and older pharmaceutical literature. The narrow margin between effective and lethal dose (3–4 seeds can be fatal) led to complete abandonment of this application. Today purely of historical-documentary value.
Preparation & dosage
Homeopathic use of Laburnum anagyroides (mother tincture and potencies D6–D30) for exhaustion, headaches and convulsive tendencies in classical homeopathy. From potency D6 onward the preparations contain no pharmacologically active cytisine amount and are considered safe; mother tincture and low potencies remain highly toxic, however.
Preparation & dosage
Wartime emergency use as tobacco substitute: during World War II laburnum seeds were smoked by German and Russian soldiers as a cheap, readily available tobacco substitute — cytisine produces a nicotine-like effect at the same receptor. The unpredictable dose (cytisine content up to 3 % in seeds) made this practice highly risky. Pure cultural phenomenon, no application recommendation.
Preparation & dosage
⚠ External use only
STRONGLY TOXIC — ALL PLANT PARTS, ESPECIALLY THE UNRIPE, PEA-LIKE SEEDS AND SEED PODS. Laburnum anagyroides contains up to 3 % cytisine in the seeds, approx. 1 % in flowers and approx. 0.5 % in leaves; additionally N-methylcytisine, anagyrine and the pyrrolizidine alkaloid laburnine. Lethal dose for adults: as few as 3–4 unripe pods, 15–20 seeds or approx. 10 flowers are considered potentially fatal; the threshold for children is substantially lower. In Central Europe laburnum is the most common cause of severe plant poisoning in children, because the pretty, pea-shaped seed pods invite play and tasting. Cytisine acts as a partial agonist at the nicotinic acetylcholine receptor (nAChR, primarily α4β2 subtype): initial stimulation of the central nervous system and autonomic ganglia, then depression progressing to seizures and respiratory paralysis. Symptoms (onset 15–60 min after ingestion): burning in mouth and throat, nausea, massive vomiting (often self-protective), salivation, abdominal pain, mydriasis, dizziness, sweating, tachycardia, hallucinations, tonic-clonic seizures, loss of consciousness, respiratory paralysis. Fatal poisonings are relatively rare thanks to rapidly setting in emesis but are documented. In suspected poisoning IMMEDIATELY call emergency services (112 in Europe / 911 in North America) and poison control. Treatment: symptomatic — activated charcoal, gastric lavage in early phase, benzodiazepines for seizures, ventilation for respiratory paralysis. No specific antidote. Risk of confusion: unripe pods may be mistaken by children for pea, bean or black-locust pods. No self-medication, no lay use. Bees can also take up cytisine in nectar/pollen — beekeeper caution required.
Cytisine is teratogenic according to animal experiments and older human data — it crosses the placental barrier and can cause fetal malformations (skeletal anomalies; the related "crooked calf disease" in cattle, caused by anagyrine, serves as a model). Any oral use of cytisine (including Tabex) as well as any exposure to plant parts during pregnancy is strictly contraindicated.
Cytisine presumably passes into breast milk (lipophilic, low molecular weight) and may induce nicotinic effects (tachycardia, vomiting, seizure tendency) in the infant. Breastfeeding: strictly contraindicated.
Children are by far the most frequently affected risk group. As few as 2–3 seeds can trigger severe poisoning symptoms in a child, 5–7 seeds can be lethal. Laburnum shrubs in gardens, playgrounds, school yards and parks should — where removal is not possible — be fenced off and labelled. Parents and educators must inform children about the toxicity. If ingestion of seeds or pods is suspected: IMMEDIATELY call poison control.
Drug interactions
Nikotinersatztherapie (Pflaster, Kaugummi, Lutschtabletten, Inhalator)
Cytisine and nicotine compete at the same α4β2 nAChR; concurrent use produces additive nicotinic toxicity (tachycardia, nausea, dizziness, risk of seizures). During Tabex therapy smoking must be tapered off.
Vareniclin (Champix®/Chantix®)
Varenicline is also a partial α4β2 nAChR agonist; combination with cytisine leads to competitive displacement and unpredictable pharmacodynamics. Combination not clinically studied — avoid.
Bupropion (Wellbutrin®/Zyban®)
Bupropion independently of cytisine lowers the seizure threshold. In combination the risk of tonic-clonic seizures rises markedly. Concurrent use with cytisine is to be avoided per several national smoking cessation guidelines.
MAO-Hemmer (Tranylcypromin, Moclobemid, Selegilin)
Nicotinic sympathomimetics may precipitate hypertensive crises under MAO inhibition. Interaction extrapolated from the class of nicotinic agonists — caution or avoidance.
Cholinesterase-Hemmer (Donepezil, Rivastigmin, Galantamin, Pyridostigmin)
Increased acetylcholine levels shift receptor dynamics at the nAChR — unpredictable modulation of cytisine activity; risk of both loss of effect and desensitization. Use cautiously.
Beta-Blocker (Propranolol, Metoprolol, Atenolol)
Combination can mask cardiovascular effects (tachycardia, hypertension) induced by cytisine/nicotine. At higher cytisine doses paradoxical bradycardia possible. Monitor.
Contraindications
- Active smokers undergoing cytisine therapy (Tabex) must consistently stop smoking — additive nicotinic toxicity
- Severe coronary heart disease, recent myocardial infarction, unstable angina — nicotinic vasoconstriction and tachycardia
- Poorly controlled arterial hypertension — sympathomimetic effect of cytisine
- Epilepsy and seizure disorders — cytisine lowers the seizure threshold (nAChR activation)
- Pheochromocytoma, hyperthyroidism — additive sympathomimetic effects
- Gastrointestinal ulcers, acute gastritis — cytisine irritates the mucosa, vomiting is frequent
- Pregnancy, breastfeeding, children and adolescents under 18 years (see above)
Harvested part: all plant parts, especially seeds
- Time of day:
- Late summer/early autumn, when pods are fully brown and dry — highest cytisine concentrations are in unripe green seeds, therefore EXCLUSIVELY harvest mature seeds for pharmaceutical cytisine extraction.
- Drying:
- Spread pods in a dry, well-ventilated location; post-dry at 35–40 °C. PROTECTIVE GLOVES MANDATORY — cytisine can be absorbed through the skin. Store in labelled, child-proof containers, separately from foodstuffs and pea/bean seed stock. Harvest exclusively by pharmacists or trained botanists for Tabex production (Sopharma) or research purposes.
- Time of day:
- Late morning on dry days during full bloom (May to June); cytisine content in flowers approx. 1 %, substantially lower than in seeds but not to be underestimated.
- Drying:
- Lay flowers flat, dry at 30–35 °C in shade; process rapidly because cytisine is partially degraded by sunlight and moisture. Wear protective gloves. Use practically only for homeopathic mother tinctures or phytochemical analysis.
- Cytisin (Cytisine)AlkaloidContent: bis 3 % (Samen), ca. 1 % (Blüten), ca. 0,5 % (Blätter)
Lead alkaloid of laburnum; bicyclic quinolizidine alkaloid; partial agonist at the nicotinic acetylcholine receptor (predominantly α4β2 subtype), pharmacological structural template for varenicline. First isolated in 1865; standardized by Isaev in 1962 in Sofia. Half-life approx. 4.8 h. Mouse LD50 (i.v.) approx. 2 mg/kg. On the WHO Essential Medicines List since 2025 (smoking cessation).
- N-Methylcytisin (Caulophyllin)AlkaloidContent: Begleitalkaloid, nicht quantifiziert
Methylated derivative of cytisine; also nicotinically active, with lower central activity; contributes to overall toxicity. Also detected in Cytisus and Sophora species.
- AnagyrinAlkaloidContent: Spuren bis < 0,1 %
Quinolizidine alkaloid; pharmacologically established as cause of "crooked calf disease" — fetal skeletal malformations — in ruminants (cattle). Contributes to the teratogenic risk assessment of the plant.
- LaburninAlkaloidContent: Spuren
Pyrrolizidine alkaloid; documented for Laburnum anagyroides on German Wikipedia; potentially hepatotoxic (typical profile of the pyrrolizidine class), but present only in small amounts in the plant.
- Hydroxynorcytisin (Hydroxynorcytisine)AlkaloidContent: Spuren
Hydroxylated nor-derivative of cytisine, isolated from Laburnum anagyroides in recent phytochemical analyses (Wikidata Q104911554). Pharmacology not fully characterized; chemotaxonomic marker.
- Flavonoide (Quercetin- und Kaempferol-Glykoside)FlavonoidContent: nicht quantifiziert
Antioxidant accompanying substances in flowers and leaves; contribute partially to the golden-yellow colour of the flower racemes; pharmacologically subordinate to the alkaloids.
- Genistein und Isoflavone (Fabaceae-typisch)FlavonoidContent: nicht quantifiziert
Isoflavones as typical secondary metabolites of the legume family (Fabaceae); phytoestrogenic activity discussed in older literature; quantitatively subordinate in Laburnum compared with soy or red clover.
- Gerbstoffe und PhenolsäurenTanninContent: nicht quantifiziert
Condensed tannins and phenolic acids in bark and wood; contribute to the hardness and durability of the dark laburnum wood, historically traded as an "ebony substitute".
- [5]MonographPlacebo-Controlled Trial of Cytisine for Smoking Cessation (West et al., NEJM 2011)(accessed: 2026-05-26)
- [6]MonographCytisine versus Nicotine for Smoking Cessation (Walker et al., NEJM 2014)(accessed: 2026-05-26)
- [7]MonographCliniTox Giftpflanzen — Laburnum anagyroides Medik.: sehr stark giftig +++ (Institut für Veterinärpharmakologie und -toxikologie, Universität Zürich)(accessed: 2026-08-10)
- [4]BookPlants For A Future — Laburnum anagyroides(accessed: 2026-05-26)
- [1]WikipediaLaburnum anagyroides — Wikipedia (EN)(accessed: 2026-05-26)
- [2]WikipediaGemeiner Goldregen — Wikipedia (DE)(accessed: 2026-05-26)
- [3]WikipediaCytisine — Wikipedia (EN)(accessed: 2026-05-26)