Sentinel Spectrum is not available in the US, ingredients are slightly different. They use it in Australia. You can purchase it online….but beware, a lot of counterfeit/damaged stuff out there. I am not familiar with Advantage multi.
Sentinel is for heartworm, Advantix II for flea/tick, Frontline for flea/tick
I have heard that Frontline works best for fleas and Advantix II works best for ticks. I am not familiar with Advantage multi.
Check with your vet as to what would be best for your dog….don’t use multiple products at the same time.
