I've used Revolution since my baby could have the treatment, which was pretty much at a very young age/weight, as they come in 0-5lbs. I like it because it about covers everything, even heartworm. It's very pricey but my vet takes price comparisons, so I at least get it for a little bit less.
__________________  R.I.P. Mick & Mandy (before 2010), Mila - 4/3/15, Chloe - 2/18/16, Kimchi - 6/2/2021 |