Mushrooms can certainly be delicious in human dishes, but should never be given to our furry friends. There are 1000s of mushroom species out there, with around 100 poisonous ones, making it almost impossible to tell which ones are safe. The type of toxin released depends on the particular mushroom. The most common signs initially seen are severe stomach and intestinal problems, with vomiting, diarrhea, and intense abdominal pain being the most notable symptoms. Depending on the toxin, multiple organs, such as the liver and kidneys, can go into failure. The brain can also be affected, leading to problems with walking, abnormal pupil size, increased aggression, howling or vocalizing, and seizures. Other signs include drooling, excessive urination and defecation, increased body temperature, wheezing, and difficulty breathing. Depending on the kind of mushroom, signs can be seen in as little as 30 minutes. Because it is unclear which mushrooms will cause the most harm, any mushroom is considered a moderate risk.