Common Name
Autumn crocus, meadow saffron
Botanic Name
Colchicum autumnale, Colchicum autumnale L. (ITIS, USDA)
Plant Family
Garden or indoor potted plant
Introduced from the Mediterranean area and Asia
Animals Affected
All animals, and humans are susceptible to poisoning
Autumn crocus (Colchicum autumnale)
Toxic Principle
All parts of autumn crocuses are poisonous, the greatest concentrations of toxic alkaloids occurring in the flowers and seeds. The corm is also toxic containing 0.05% alkaloids, in contrast to 0.2% in the seeds. However, the corms are large enough to contain toxic doses of the alkaloids. The primary toxic alkaloid is colchicine, which interferes with cell mitosis. Colchicine and its related alkaloids interfere with microtubular dependent cell function's by binding to tubulin protein, thus blocking mitosis in multiple tissues.1 All animals are susceptible to the toxic effects of colchicine. Multiple organ failure is characteristic of acute colchicine poisoning. Colchicine also causes marked decreases in prolactin, insulin, glucose tolerance, and catecholamine production. An estimated lethal dose of colchicine is 0.8 mg per kilogram body weight. Another plant that is known to contain colchicine and similar alkaloids is the Glory Lilly (Gloriosa superba) which contains up to 0.36% colchicine in its tubers.
Comprising the genus of some 60 species originating in Europe and North America and West and Central Asia. Many species originate from the Mediterranean area around Turkey and the Balkans. Arising from corms, almost all species produce flowers before they produce leaves. The leaves are basal, long, linear blades. Flowers are produced singularly or clusters atop long tubes and are generally purple, pink, or white in color. In contrast to Crocus species, which have 3 stamens, Colchicum flowers each have 6 stamens and three pistils. Many species tend to flower in the fall, but others may flower in the spring. (Figures 1,2)
Severe salivation, vomiting, abdominal pain and severe hemorrhagic diarrhea.
Weakness and collapse.
Congenital Defects
Cleft palate
Maintain kidney function with intravenous fluid therapy and other supportive therapy as necessary.
Cardiovascular system
Nervous System
Renal System
Kidney failure
Reproductive System
Cleft palate in the fetus
Hepatic System
Liver failure
Colchicine can be detected in the serum and urine.
Special Notes
The best known species of the genus is Colchicum automnale, called autumn crocus as it is an autumn flowering species. This should not be mistaken for Crocus sativus, a member of the Iridaceae family, that also flowers in the autumn. The stamens of Crocus sativus flowers are the source of saffron, an expensive food coloring and spice. Animals or people who are known to have eaten any part of the bulb, flowers or seeds of the autumn crocus should be seen by a veterinarian or physician, as appropriate, as quickly as possible. References: 1.Yamada AM et al: Histological study of experimental acute poisoning of cattle by autumn crocus (Colchicum autumnale). Japanese Vet Med Sci 1998,60:949-952. 2. Gabrscek L. et al: Accidental poisoning with autumn crocus. J Toxicology - Clinical Toxicol.42:85-8, 2004. 3. Mendis S: Colchicine cardiotoxicity following ingestion of Gloriosa superba tubers. Postgraduate Med J 65:752-5, 1989.
Forced blooming of autumn crocus indoors
Glory lily (Gloriosa superba)