>>Do I use Revolution for cats or dogs, and do I use the entire dose on one rat? Thanks.

I used the one they make for the smallest weight dogs.
I used one tube but I sucked it out by the drop with a syringe & needle then put just a drop about 0.01 cc on each male rat at the nape of the neck just like with a dog. I used 0.05 on the smaller females.
You should keep the rats apart until it dries on them- which only takes a couple of minutes or so.
I remember my vet has a set dose for this but I don't recall what it is, she told me that a drop was fine as long as it works but I could've actually used a little more without harm to them. Hopefully your own vet will have a set dose to give you.

Then the next thing I did was I bleached their cages & everything in them. I went over the wire & cage bottom with dog flea shampoo- just in case any lice were wandering around in there.
What I love about Revolution is that when the lice eggs hatch, it's still working on them so it kills what hatches when they hatch then the eggs are gone & no more lice!
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PHRatz