Frontline for kitten?

I found out that Jack is old enough to use Frontline on I'm going to put it on both kitties for a while to make sure all the fleas are dead and gone. My question is, do I put the whole applicator's worth on Jack or maybe just half? He's so little still and it seems like quite a bit for such a little guy, though the instructions say there are no weight restrictions just age. What do you think I should do?

If you don't use it all, it will not work. Frontline can be used on kittens as young as 8 weeks of age. There is no exact "sizes" for it, either....like with Revolution.

I would use it all.

Ziggy is fully grown and yet is still a very small cat, she looks about 6 months old. I use she whole sachet for her. Some frontine products have weight guidlines like the spray, but if it hasn't, go by the age.