You’re right about vets being sales people and that’s also good advice to ask a groomer.
groomers are arch nemesis of vets..if you have a few rounds of dogs etc you know the role of vets have changed over the years and you're not going to get out of the visit- no matter what decision you make..$300 easy. i told my vet about how my dog acted after i gave her that medicine (it says right on the box 'causes seizures in some dogs') and she gave me doggie xanax..great! cover something with something else to keep the expensive med train going.
fvck that. don't give your dogs shit. buy the Bio Groom for flea protection and that's all you need once per month. once a year HW test to make sure. do not buy the medicine.
A healthy dog shouldn't need all what vet wants you to buy..what did we do before it was invented?