I USED To use Revolution but after a few members pointed out some studies that showt he death rate is higher in this than others (However, it could just be because it is more widely used) I have decided to use Interceptor this year which is just for heartworm- no flea/tick. Layla is not an "outdoorsey" kinda gal and I feel the pros out weight the cons for us- I like to use AS LITTLE meds as possible and will probably use an herbal remedy if we are going to be outside in the bush- lol which i don't see us doing