Stink bugs are not poisonous to dogs. While dogs may eat stink bugs, the bugs do not contain toxins or venom harmful to them. However, the chemicals stink bugs release as a defense can irritate a dog's mouth and gastrointestinal tract, possibly causing symptoms like vomiting, excessive drooling, and mouth irritation. These symptoms are generally temporary and not serious. In rare cases, if a dog eats a large number of stink bugs, it might form a hard mass in the stomach requiring veterinary attention. Overall, stink bugs are not toxic but can cause mild discomfort in dogs if ingested.
