Are plums poisonous to dogs?

The flesh of the plum is not poisonous, but it is not uncommon for a dog to develop diarrhoea after it eats plums. The pit contains a substance that can be poisonous to dogs, but the dog has to chew and break the pit and eat many of them in order to become affected. If you have a small dog that has eaten a plum, the pit can be dangerous because it can get stuck in the intestines while passing through the digestive tract.