Dogs may not be able to smell isoniazid. If isoniazid is mixed into food, the dog will not be able to smell it and will probably eat it and die, so it is best not to let the dog in the food. Picking up random things to eat outside will prevent your dog from being poisoned.
Tips:
When you take your dog out, you must wear a leash and train your dog not to pick up things. Eat, do not eat food given by others, etc., and let the dog eat at a fixed time and place.