When we started Snowbirding, we discovered that Florida Fleas are far more savage than Michigan fleas; and poor Jimmy was allergic to the flea bites. He was miserable enough from the swollen bites, but to top it all off, they made him break out in hives. yeeesh. A trip to the local vet ensued, where we were given Bravecto (a chewable dose). It worked wonders - I would actually find dead fleas on his fur. The next year, I went to FL with Bravecto - and the moment the same old trouble started, we dosed him and he was fine. So I have a lot of faith in the effectiveness of the product, but a part of me was squeamish about something that remained in his systems for 3 months.
My daughter told me to try giving Jimmy "Brewer's Yeast with Garlic" tablets - I give both dogs 1 tablet per 10 lbs, every morning. They LIKE it - gladly eat it out of my hand or mixed into their food; and for my dogs, in Florida, it works very well. Once in a while I might see one scratch; but Jimmy has not suffered any allergic reactions to the occasional bite.
My daughter says it keeps the ticks off her dog, who has free roam of 10 acres of (Michigan) wild fields; but I DID have to remove 2 (Florida) ticks from Jimmy's nose a few weeks ago.