✕ Toxic

Autumn Crocus

Colchicum autumnale

Autumn Crocus (Colchicum autumnale) is one of the most dangerous plants a cat can encounter, and should not be confused with the common spring-blooming crocus (Crocus spp.), which is far less toxic. It contains colchicine, a potent alkaloid that halts cell division by preventing microtubule formation — targeting the body's fastest-dividing cells, including those in the gut lining, bone marrow, and kidneys. Crucially, symptoms can be delayed by 2 to 12 hours after ingestion, making early veterinary intervention critical even when the cat appears unaffected.

Important Notes

Symptoms: Severe vomiting, bloody diarrhea, burning pain in the mouth and throat, followed hours later by bone marrow suppression (anaemia, reduced white blood cells), kidney failure, and respiratory failure.

All parts are lethal: The bulb (corm) is the most toxic, but flowers, leaves, and seeds all contain colchicine in dangerous concentrations.

Action: This is a life-threatening emergency. Take the cat to a vet immediately — do not wait for symptoms.

Potentially Toxic Parts

All parts of the plant

Bulbs

Possible Symptoms Reported in Cats

Respiratory Distress (Abnormal breathing patterns, difficulty breathing)

Respiratory · Can occur as the toxicity progresses, often days after exposure, or within hours in acute cases.

Liver Damage (Hepatotoxicity) and Kidney Failure (Renal Failure)

Renal · Often delayed by days after the initial ingestion.

Shock (Pale gums, abnormal heart rate, lethargy, weak pulse)

Cardiac · Can occur within hours or as the condition deteriorates.

Severe Vomiting (often bloody), Diarrhea (often bloody), Abdominal Pain, Drooling, and Difficulty Swallowing

Gastrointestinal · Symptoms often appear immediately or within hours of ingestion,

Bone Marrow Suppression

Hematological · Delayed (as it affects cell division and blood cell production).

Seizures

Neurological · Variable; often associated with advanced toxicity.

Liver Damage (Hepatotoxicity)

Hepatic

Disclaimer: This summary was compiled from multiple sources and is for informational use only. It is not a diagnosis or treatment plan. Toxicity can vary based on the substance, amount, plant part, and individual cat. If you think your cat may have been exposed to a toxic substance, contact a veterinarian right away.