I washed my 10 year old chihuahua with harts flea and tick shampoo right before we took her to the vet for her routine vaccinations. The very next day she had diarrhea and was very lethargic. I thought symptoms were related to her rabies shot. After a week she had gotten worse and had hives all over so we took her in for a re check. She was given a few medications for the allergic reaction and has since gotten better skin wise. However it is now 2 weeks later and she is still very lethargic, has hardly no appetite and looks like she is wasting away. We are really considering putting her down at this point. I looked up the shampoo and heard all the traumatic stories and now know we have all fallen victim as well.