We bathed our dog in Hartz ultra guard when he had fleas, and he started having side effects within a few hours – shaking all over, laying without energy, not wanting to be picked up, biting you if you tried (not normal), etc. We called the vet, and they told us to bring him in. Good thing we did. Evidently they see this happen frequently, and gave him a shot to counteract the POISON in the shampoo. They gave us an 800 number to call if he didn’t get better, since we would have to take him an hour to Chesapeake to get a second shot (over the weekend the vet would be closed). It is unbelievable to me that this shampoo is still SOLD, despite the fact the dogs and cats have died and/or been disabled for life.(as verified by vet). But why should I be surprised…..this is the U.S.A. , right? All they do is put a warning label on it, and continue to make millions, despite what it does to health.