poor kitty! I hope he is feeling better now! The advantage in the orange tube if for "kittens 8 weeks and older and 9 pounds and under"" the purple tube is for cats and kittens 8 weeks and older and over 9 pounds"
I'm sure the little guy must have manage to lick some of the product off, which of course tastes gross, I'm sure!
BTW, the package says the "product is bitter tasting and salivation may occur for a short time if the cat licks the product immediatley after treatment"
I use advantage, and I beleive it is a good product. I live in Florida where the flea problem is wicked, and I think that it works great! Matter of fact, my Sammy was totally infested with fleas
when I got him at 8 weeks ( he and his brother's and sisters were on their way to the pound, the owner could'nt be bothered anymore ) which of course explains why the poor baby was infested! After 2 treatments, the flea were completley gone.
However, advantage does'nt kill ticks, so if your little one will be spending some time outside, I would use Frontline.
I hope this helps you a bit