Stink bugs are not toxic to cats. However, their defensive secretions can irritate a cat's mouth, digestive tract, and eyes, potentially causing symptoms like drooling, vomiting, diarrhea, and irritation. Most cats will experience mild or no symptoms, but in some cases, gastrointestinal upset or oral irritation may occur. Serious effects are rare, but if a cat eats many stink bugs, there could be a risk of a digestive blockage, which would require veterinary attention. Overall, stink bugs do not poison cats but can cause temporary discomfort.