ASPCA Blog: Ask the APCC: Are Pomegranates Harmful to Dogs?
While the ripe fruit of the pomegranate is considered to be edible by humans, various parts of the plant contain alkaloids and tannins, which can cause significant GI irritation and even central nervous system depression in pets, depending on the amount ingested. Therefore, we would recommend not allowing your dog to consume the fallen fruit or other parts of the plant.