Periwinkle (Vinca rosea) finds it way into many households because of its attractive blue flowers and dark green foliage, but it’s not a good choice for pet owners. Also known as vinca or running myrtle, periwinkle is toxic to dogs, cats and horses. Keep pets away from the plant either by removing it completely or fencing it off so access is impossible.
Toxicity
Periwinkle contains several toxic alkaloids, any of which can mean trouble for your dog. These include vinblastine, yohimbine and vincristine, substances that can be useful in medicine, such as chemotherapy because they stop cell reproduction, but can also have serious side effects.
Poisoning Symptoms
Symptoms of periwinkle poisoning include gastric reactions such as diarrhea and vomiting. Your pet may also have neurological or other symptoms such as tremors, dangerously low blood pressure, coma and seizures. Death can occur. The degree to which your dog is affected depends on his level of sensitivity as well as how much of the plant he’s ingested.
Treatment
Do not induce vomiting; vomiting can make your dog worse. Depending on your dog’s symptoms, his vet may counter the toxins with injections, have the dog swallow activated charcoal, or provide supportive care such as administering fluids. Don’t wait for symptoms to show up before calling your vet; if you suspect your dog has ingested any part of the periwinkle plant, contact your veterinarian immediately.