Cicadas aren’t poisonous or toxic to dogs, however, cicadas have a hard exoskeleton that can be difficult to digest if your dog gorges himself – causing an upset stomach, vomiting, and diarrhea. Also, consider if you’ve sprayed any chemicals over areas where cicadas have been underground. The best advice for your pup? Try to keep your dog away from opportunities where he can eat cicadas. If your dog does experience severe vomiting or diarrhea, contact your vet asap.