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Colchicum autumnale
Toxic🐾Herbstzeitlose · (Colchicum autumnale)
Autumn-crocus family (Colchicaceae)
Description
Each autumn the meadow saffron pushes its pale lilac flowers straight out of bare soil, weeks before its strap-shaped leaves appear the following spring — a habit that earned it folk names like 'naked lady'. A member of the Colchicaceae, it favours damp meadows across Europe and is harvested for its corm and flowering parts, which are rich in alkaloids, chiefly colchicine, alongside flavonoids. Pharmaceutical colchicine, isolated and precisely standardised, is an established treatment for acute gout flares and familial Mediterranean fever, administered strictly under medical supervision. The raw plant itself is among the most toxic in Central Europe: even minute amounts of corm or seed can be lethal to people and pets alike, and no safe self-dosing margin exists. Home use of any part of the plant must always be avoided.
🌿 Risk of confusion — read before wild-harvesting!
Colchicum autumnale (autumn crocus) is one of the most toxic plants in Central Europe. Animal hazard: highly toxic to dogs, cats and horses (ASPCA) — even small amounts can be fatal.
External use only!
This plant must NOT be taken internally. Use only as compress, salve, or bath.
CONTRAINDICATED during pregnancy
Colchicine is teratogenic and embryotoxic in animal studies. Contraindicated even as a pharmaceutical drug in pregnancy. The plant itself is absolutely contraindicated.
CONTRAINDICATED during breastfeeding
Colchicine is excreted into breast milk. Breastfeeding is contraindicated even with pharmaceutical use. The plant is absolutely contraindicated.
CONTRAINDICATED for children
No application of plant preparations from Colchicum autumnale in children and adolescents. Pharmaceutical colchicine may only be used in children under strict medical indication (e.g. FMF).
Critical drug interactions with:
CYP3A4-Inhibitoren (z. B. Clarithromycin, Erythromycin, Itraconazol) · P-Glykoprotein-Inhibitoren (z. B. Ciclosporin, Verapamil)
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.
Colchicine, the active compound isolated from Colchicum autumnale, is an approved pharmaceutical for treating acute gout flares. The placebo-controlled double-blind study by Terkeltaub et al. (2010) showed that low-dose colchicine (1.2 mg + 0.6 mg after 1 hour) is as effective as high-dose protocols, with a significantly better tolerability profile. IMPORTANT: This indication applies exclusively to standardised pharmaceutical colchicine preparations (e.g. Colchicum-Dispert®). The plant itself is NOT suitable for self-administration — no therapeutic window exists; fatalities have been documented.
Preparation & dosage
Pharmaceutical colchicine (active compound from Colchicum autumnale) is the first-line therapy for familial Mediterranean fever (FMF). Levy and Eliakim (1977) and Peters et al. (1978) documented in early prospective studies the prevention of fever attacks and prophylaxis of AA amyloidosis with long-term use. Today recognised internationally as the standard therapy. Only as a pharmaceutical, not as a plant product.
Preparation & dosage
In the COLCORONA analysis (Tardif et al., published in Journal of Diabetes and Clinical Research 2021), pharmaceutical colchicine was investigated in outpatient COVID-19 patients. Colchicine inhibited the excessive inflammatory response (inflammasome activation) and, in PCR-confirmed cases, reduced the combined endpoint risk (hospitalisation, ventilation, death). The study pertains to pharmaceutical colchicine, not plant extracts.
Preparation & dosage
Sources: [4]
Pharmaceutical colchicine (from Colchicum autumnale) is a documented treatment for Behçet's disease. In the randomised double-blind trial by Yurdakul et al. (2001), colchicine significantly reduced the frequency of skin manifestations and joint attacks in Behçet's patients. Only as a prescription pharmaceutical.
Preparation & dosage
Sources: [5]
Historically in folk medicine, Colchicum autumnale was used in European folk medicine and by Arab physicians of the Middle Ages (Ibn Sina / Avicenna, c. 980–1037) for joint pain, gout, and dropsy. Due to the lack of a therapeutic window and documented fatalities from colchicine poisoning, any folk-medicine self-administration of the plant is today STRICTLY CONTRAINDICATED. Historical documentation without any recommendation to follow.
Preparation & dosage
In the 19th and early 20th centuries, a standardised Colchicum seed extract (Colchicinum crudum) was used in phytotherapy before pure colchicine was isolated. Maud Grieve documents its use for gout in 'A Modern Herbal' (1931). The historical tincture had unpredictable active substance content and caused poisonings. Today obsolete and STRICTLY CONTRAINDICATED — listed here for historical documentation only.
Preparation & dosage
Colchicum autumnale is known homeopathically as the remedy 'Colchicum' and is used for gout, acute joint pain, and digestive complaints, among other indications. Homeopathic potentisation (D4 and above) contains no pharmacologically relevant amounts of colchicine. Homeopathic Colchicum preparations are legally available and considered safe when correctly potentised.
Preparation & dosage
Sources: [6]
⚠ External use only
Colchicum autumnale (autumn crocus) is one of the most toxic plants in Central Europe. The active compound colchicine inhibits mitosis through tubulin binding; as little as 0.1 mg/kg body weight can be lethal. All plant parts are toxic — seeds and corm especially. SELF-ADMINISTRATION AS A PLANT PREPARATION IS ABSOLUTELY CONTRAINDICATED. Therapeutic use is restricted exclusively to pharmaceutically standardised colchicine medications given under medical supervision with dose control. Colchicine has no safe self-dosable amount as raw material. Poisoning symptoms: nausea, vomiting, diarrhoea, kidney damage, bone marrow failure, death. Animal hazard: highly toxic to dogs, cats and horses (ASPCA) — even small amounts can be fatal. ASPCA classification (accessed 2026-08-10): toxic to dogs and cats.
Colchicine is teratogenic and embryotoxic in animal studies. Contraindicated even as a pharmaceutical drug in pregnancy. The plant itself is absolutely contraindicated.
Colchicine is excreted into breast milk. Breastfeeding is contraindicated even with pharmaceutical use. The plant is absolutely contraindicated.
No application of plant preparations from Colchicum autumnale in children and adolescents. Pharmaceutical colchicine may only be used in children under strict medical indication (e.g. FMF).
Drug interactions
CYP3A4-Inhibitoren (z. B. Clarithromycin, Erythromycin, Itraconazol)
CYP3A4 inhibition dramatically increases colchicine plasma levels; deaths from colchicine toxicity (bone marrow failure, multi-organ failure) documented in combination with macrolide antibiotics.
P-Glykoprotein-Inhibitoren (z. B. Ciclosporin, Verapamil)
P-gp transporter inhibition reduces renal and biliary colchicine elimination; massive plasma level increase possible; life-threatening.
HMG-CoA-Reduktase-Hemmer (Statine)
Additive risk of myopathy and rhabdomyolysis with concurrent colchicine use; particularly elevated in renal insufficiency.
Contraindications
- Any self-administration as a plant product (tea, tincture, fresh plant) — absolutely contraindicated
- Severe renal insufficiency (GFR < 30 ml/min) — pharmaceutical colchicine also contraindicated
- Severe hepatic insufficiency — colchicine is hepatically metabolised; accumulation and toxicity risk
- Pregnancy and lactation
- Combination with strong CYP3A4 inhibitors without dose adjustment (e.g. clarithromycin, ciclosporin) — fatalities documented
Harvested part: flowering plant / corm
- Time of day:
- Harvest exclusively for scientific or pharmaceutical purposes by trained personnel. Seeds ripen in midsummer (July–August). Protective gloves and goggles MANDATORY.
- Drying:
- Drying at max. 40 °C under strictly controlled conditions (pharmaceutical drug production). Never dry for domestic use.
- Storage:
- 24 months — Dry, cool, protected from light in sealed containers. Exclusively for pharmaceutical processing or research laboratories.
- Time of day:
- Corms are dug up after the foliage dies back in early summer (June–July) — exclusively for pharmaceutical extraction of colchicine. WARNING: Avoid skin contact with plant sap. Protective equipment obligatory.
- Drying:
- Drying and further processing only in pharmaceutical facilities. No domestic processing.
- Storage:
- 12 months — Pharmaceutical storage; labelled as toxic substance. Absolutely not accessible to laypersons.
- ColchicineAlkaloidContent: 0,1–0,8 %use.plant_part.bulb
Tropolone alkaloid; binds tubulin and inhibits the mitotic spindle; the lead compound of Colchicum autumnale and the only therapeutically used active substance; no therapeutic window as raw material.
- 3-DemethylcolchicineAlkaloidSeed
Structurally related alkaloid; also antimitotic but less pharmacologically exploited than colchicine.
- Demecolcine (Colcemid)AlkaloidContent: < 0,05 %Seed
N-Deacetyl-N-methylcolchicine; used in cell biology for mitosis arrest; less potent than colchicine.
- ColchamineAlkaloidSeed
Further Colchicum alkaloid; cytotoxic; used in experimental cancer research (topical application for skin lesions).
- CornigerinAlkaloiduse.plant_part.bulb
Thiocolchicine-related alkaloid from Colchicum cornutum; structurally belonging to the Colchicum alkaloid group.
- Flavonoide (Luteolin, Apigenin)FlavonoidAerial parts
Detected in aerial plant parts; antioxidant properties, though not therapeutically relevant — toxicity from alkaloids dominates the safety profile.
- Stärke und ZuckerPolysaccharideuse.plant_part.bulb
Storage carbohydrates in the corm; of no pharmacological significance but increase the colchicine fraction of the edible plant mass.
- [1]MonographTerkeltaub RA et al. (2010): High versus low dosing of oral colchicine for early acute gout flare — randomized double-blind study. Arthritis & Rheumatism 62(4):1060–1068(accessed: 2026-05-24)
- [2]MonographLevy M, Eliakim M (1977): Long-term colchicine prophylaxis in familial Mediterranean fever. BMJ 2(6090):808–810(accessed: 2026-05-24)
- [3]MonographPeters RS, Lehman TJA, Schwabe AD (1978): Long term colchicine prophylaxis in familial mediterranean fever (FMF). Gastroenterology 75(3):492–495(accessed: 2026-05-24)
- [4]MonographTardif JC et al. (2021): Colchicine in COVID-19 — The Colcorona Trial. Journal of Diabetes and Clinical Research 3(1)(accessed: 2026-05-24)
- [5]MonographYurdakul S et al. (2001): A double-blind trial of colchicine in Behçet's syndrome. Arthritis & Rheumatism 44(11):2686–2692(accessed: 2026-05-24)
- [9]MonographASPCA Animal Poison Control — Autumn Crocus (Colchicum autumnale)(accessed: 2026-06-03)
- [10]MonographASPCA Animal Poison Control — Autumn Crocus (Colchicum autumnale)(accessed: 2026-08-10)
- [11]MonographCliniTox Giftpflanzen — Colchicum autumnale L.: sehr stark giftig +++ (Institut für Veterinärpharmakologie und -toxikologie, Universität Zürich)(accessed: 2026-08-10)
- [7]BookPlants For A Future (PFAF): Colchicum autumnale — Autumn Crocus(accessed: 2026-05-24)
- [8]BookMaud Grieve: A Modern Herbal — Colchicum (botanical.com, 1931)(accessed: 2026-05-24)
- [6]WikipediaWikipedia DE: Herbstzeitlose (Colchicum autumnale)(accessed: 2026-05-24)