Safety verdict
Consulted references classify the plant as toxic or irritating for that pet type.
Pet ingestion lookup
My dog ate Madagascar Periwinkle - what should I do?
Catharanthus roseus
Potentially toxic
Contact your veterinarian or an animal poison-control resource now, especially if any amount was chewed or swallowed.
Verified against ASPCA/provenance audit 2026-05-06 on May 6, 2026.
Signs to watch for
Vomiting, diarrhea, lethargy, and potential tremors or ataxia.
Escalation note
The plant contains toxic alkaloids that can cause serious illness if consumed. Seek veterinary care promptly if your dog has ingested any part of this plant.
First aid at home
Remove plant material from your dog's mouth and collect a leaf or two so the vet can confirm the species. Call Pet Poison Helpline before driving in. Do not induce vomiting unless directed.
What to watch for
Vomiting and diarrhea are the typical first signs, often paired with depression and loss of coordination. With a larger dose, watch for tremors, seizures, hypotension (weakness, slow capillary refill), and rare cases of coma. Toy breeds and puppies reach toxic doses much faster than larger dogs.
Time window
Mild GI signs usually start within a few hours. Most dogs recover within 24 hours with fluids and supportive care; more serious cases may need 48 to 72 hours of monitoring.
When to call the vet
Call Pet Poison Helpline (1-800-213-6680) or your vet as soon as you suspect ingestion. Bring the dog in immediately for any neurological signs — tremors, ataxia, seizures — or for repeated vomiting that doesn't settle within an hour or two.
What this means for your dog
Madagascar periwinkle is toxic to dogs. The vinca alkaloids inside it are powerful enough to be used in human chemotherapy; in dogs, ingestion ranges from GI upset on the low end to seizures, tremors, and low blood pressure on the high end. Severe poisonings are uncommon because the plant tastes bitter, but small dogs and curious puppies are most at risk.
Sources: ASPCA, Pet Poison Helpline, NC State Extension.
Source references
Poison-control resources
This page summarizes source-bound plant-safety information and is not veterinary advice.