I have a sample of Advantage multi from my vet for our puppy, so I think I will use that for this month. I went on 1800petmeds.com and did a comparison of all the products and It seems that K9 Advantix and Interceptor are the best. I have been using Heartgard plus and Frontline on our 9lb yorkie and it has been fine, but why not use the best
!!! So I will start them both on that combo I think!