Frontline For Dogs Do Store Bought Flea And Tick Meds Work The Same As Vet Brands Like Frontline For Dogs?

Do store bought flea and tick meds work the same as Vet brands like Frontline for dogs? - frontline for dogs

I have always been my first line of boxers bought 4 years, but the high prices, I saw three applications at Walmart for $ 15. If they were so effective? I want to do what is best for my dog. Thank you!