←
Madagascar Periwinkle
Catharanthus reseus
Madagascar Periwinkle (Catharanthus roseus) is a common ornamental flowering plant that is severely toxic to cats. It contains vinca alkaloids — primarily vincristine and vinblastine — the same compounds used as chemotherapy drugs in cancer treatment. Even small amounts can cause serious, life-threatening toxicity in cats.
Important Notes
Toxic compounds: vinca alkaloids — vincristine, vinblastine, vinorelbine; all parts of the plant are toxic
Mechanism: vinca alkaloids inhibit cell division by binding to tubulin, disrupting the mitotic spindle; this damages rapidly dividing cells including bone marrow and GI epithelium
Symptoms: vomiting, diarrhea, severe weakness, low blood pressure, neurological signs (tremors, seizures); bone marrow suppression may develop over days
Despite its cheerful appearance, this plant is as dangerous as chemotherapy agents
Any suspected ingestion is a veterinary emergency
Potentially Toxic Parts
Entire Plant
Possible Symptoms Reported in Cats
Pharyngeal (throat) pain, abdominal pain, severe diarrhea, and dehydration
Gastrointestinal
Peripheral nerve damage
Gastrointestinal
Bone marrow suppression (depression)
Gastrointestinal
Cardiovascular damage
Cardiac
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.