Both the British and American Veterinary Medical Associations (I am a member of both) have reported these concerns in their professional journals. In addition, the feces of dogs given oral insecticides and antiparasitic drugs should always be picked up and disposed of with other household waste. : I have expressed my concerns over many veterinarians prescribing the immune system-suppressing drug Apoquel on my website (drfoxonehealth.com). There may be other environmental allergens affecting your dog, so I would give him 1 teaspoon of local bee pollen daily with his food. There are ways to prevent these problems, and all dog owners should consult with their veterinarians and animal behaviorist referrals.