How long do I have to wait to put Advantage on my cat since I put Frontline on it 2 and 1/2 weeks ago?

Question

I put Frontline on my cat about 2 and 1/2 weeks ago and it didn't help with the fleas. I bought some Advantage but I don't know how much longer I have to wait to put it on. Any answers?

Answer 1

Another 2.5 weeks.