Yes, the periwinkle plant can be toxic if ingested improperly. The plant contains several other toxic compounds that can cause adverse effects. Symptoms of periwinkle poisoning may include nausea, vomiting, diarrhea, and abdominal pain. In severe cases, it can lead to more serious conditions such as neurotoxicity and cardiotoxicity. Hence, it is crucial that the plant or its extracts are only used under professional guidance.
