Yesterday I was talking to someone about cats and a question came up. About three years ago my friend had a very healthy and well cared for 5 year old female cat. Since kitty went outside at times and there are woods behind their house, she asked her vet about flea and tick protection, the vet gave her Frontline. She's a health care professional and knows the importance of following directions to the letter. She applied it exactly as directed but kitty died 2 days later. There were no signs of injury, no change of food, the only different thing was the Frontline. When she called, her vet said he never saw or heard of any problems with Frontline. Is anyone aware of any problems or side effects from Frontline?